Category: Class 12

Students can Download Tamil Nadu 12th Physics Model Question Paper 4 English Medium Pdf, Tamil Nadu 12th Physics Model Question Papers helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

TN State Board 12th Physics Model Question Paper 4 English Medium

General Instructions:

• The question paper comprises of four parts.
• You are to attempt all the parts. An internal choice of questions is provided wherever applicable.
• All questions of Part I, II, III, and IV are to be attempted separately.
• Question numbers 1 to 15 in Part I are Multiple Choice Questions of one mark each.
  These are to be answered by choosing the most suitable answer from the given four
  alternatives and writing the option code and the corresponding answer
• Question numbers 16 to 24 in Part II are two-mark questions. These are to be answered
  in about one or two sentences.
• Question numbers 25 to 33 in Part III are three-mark questions. These are to be answered
  in about three to five short sentences.
• Question numbers 34 to 38 in Part IV are five-mark questions. These are to be answered
  in detaiL Draw diagrams wherever necessary.

Time: 3 Hours
Max Marks: 70

Part – I

Answer all the questions. Choose the correct answer. [15 x 1 = 15]

Question 1.
Which charge configuration produces a uniform electric field?
(a) point charge
(b) infinite uniform line charge
(c) uniformly charged infinite plane
(d) uniformly charged spherical shell
Answer:
(c) uniformly charged infinite plane

Question 2.
The work done in carrying a charge Q, once round a circle of radius R with a charge Q₂ at the centre is  ………….
(a) \(\frac{\mathrm{Q}_{1} \mathrm{Q}_{2}}{4 \pi \varepsilon_{0} \mathrm{R}^{2}}\)
(b) Zero
(c)  \(\frac{\mathrm{Q}_{1} \mathrm{Q}_{2}}{4 \pi \varepsilon_{0} \mathrm{R}} \)
(d) infinite
Answer:
(b) Zero
Hint: The electric field is conservative. Therefore, no work is done in moving a charge around a closed path in a electric field.

Question 3.
The internal resistance of a 2.1 V cell which gives a current of 0.2 A through a resistance of 10 Ω is……………………..
(a) 0.2 Ω
(b) 0.5 Ω
(c) 0.8 Ω
(d) 1.0 Ω
Answer:
(b) 0.5 Ω

Question 4.
An electron moves straight inside a charged parallel plate capacitor of uniform charge density σ. The time taken by the electron to cross the parallel plate capacitor when the plates of the capacitor are kept under constant magnetic field of induction \(\overrightarrow{\mathrm{B}}\) is ……….


Answer:
(d)

Question 5.
In a series resonant RLC circuit, the voltage across 100Ω resistor is 40 V. The resonant frequency co is 250 rad/s. If the value of C is 4 pF, then the voltage across L is……………….
(a) 600 V
(b) 4000 V
(c) 400 V
(d) IV
Answer:
(c) 400 V

Question 6.
During the propagation of electromagnetic waves in a medium:
(a) electric energy density is double of the magnetic energy density
(b) electric energy density is half of the magnetic energy density
(c) electric energy density is equal to the magnetic energy density
(d) both electric and magnetic energy densities are zero
Answer:
(c) electric energy density is equal to the magnetic energy density

Question 7.
First diffraction minimum due to a single slit of width 1.0 x 10^-5 cm is at 30°. Then wavelength of light used is, …………………
(a) 400 Å
(b) 500 Å
(c) 600 Å
(d) 700 Å
Answer:
(b) 500 Å
Hint. For diffraction minima, d sin θ = nλ
\(\lambda=\frac{d \sin \theta}{n}=\frac{1 \times 10^{-5} \times 10^{-2} \times \sin 30^{\circ}}{1}=0.5 \times 10^{-7}\)
λ = 500 Å

Question 8.
The sky would appear red instead of blue if
(a) atmospheric particles scatter blue light more than red light
(b) atmospheric particles scatter all colours equally
(c) atmospheric particle scatter red light more than blue light
(d) the sun was much hotter
Answer:
(c) atmospheric particle scatter red light more than blue light

Question 9.
Kinetic energy of emitted electron depends upon
(a) frequency
(b) intensity
(c) nature of atmosphere surrounding the electron
(d) none of these
Answer:
(a) frequency
Hint: Kinetic energy of emitted electron depends on the frequency of incident radiation.

Question 10.
The ratio between the first three orbits of hydrogen atom is…………….
(a) 1:2:3
(b) 2:4:6
(c) 1:4:9
(d) 1:3:5
Answer:
(c) 1:4:9
Hint :
E_n = \(\frac{-13.6 \times z^{2}}{n^{2}}\)
n = 1; E₁ =- 13.6 eV/ atom
n = 2; E₂ = – 3.4 eV/ atom
n = 3; E₃ = -1.51 eV/atom                             ’
The ratio of three orbits E₁ : E₂ : E₃ = 13.6 : 3.4 : 1.51 = 1 : 4 : 9

Question 11.
Bohr’s theory of hydrogen atom did not explain fully
(a) diameter of H-atom
(b) emission spectra
(c) ionisation energy
(d) the fine structure of even hydrogen spectrum
Answer:
(d) the fine structure of even hydrogen spectrum
Hint: Bohr theory could not explain the five structure of hydrogen spectrum.

Question 12.
If a half-wave rectified voltage is fed to a load resistor, which part of a cycle the load current will flow?
(a) 0° – 90°
(b) 90° – 180°
(c) 0° – 180°
(d) 0° – 360°
Answer:
(c) 0° – 180°

Question 13.
Diamond is very hard because ……………..
(a) it is covalent solid
(b) it has large cohesive energy
(c) high melting point
(d) insoluble in all solvents
Answer:
(b) it has large cohesive energy

Question 14.
The internationally accepted frequency deviation for the purpose of FM broadcasts.
(a) 75 kHz
(b) 68 kHz
(c) 80 kHz
(d) 70 kHz
Answer:
(a) 75 kHz

Question 15.
The blue print for making ultra durable synthetic material is mimicked from
(a) Lotus leaf
(b) Morpho butterfly
(c) Parrot fish
(d) Peacock feather
Answer:
(c) Parrot fish

Part – II

Answer any six questions in which Q. No 17 is compulsory.   [6 x 2 = 12]

Question 16.
Define ‘electric flux’.
Answer:
The number of electric field lines crossing a given area kept normal to the electric field lines  is called electric flux. Its unit is N m² C^-1. Electric flux is a scalar quantity.

Question 17.
Determine the number of electrons flowing per second through a conductor, when a current of 32 A flows through it.
Answer:
I = 32A, t= 1 s
Charge of an electron, e = 1.6 x 10^-19 C
The number of electrons flowing per second, n =?

Question 18.
Define magnetic flux.
Answer:
The number of magnetic field lines crossing per unit area is called magnetic flux φ_B
\(\phi_{\mathrm{B}}=\overrightarrow{\mathrm{B}} \cdot\overrightarrow{\mathrm{A}}=\mathrm{B} \mathrm{A} \cos \theta=\mathrm{B} \perp \mathrm{A}\)

Question 19.
Give any one definition of power factor.
Answer:
The power factor is defined as the ratio of true power to the apparent power of an a.c. circuit.
It is equal to the cosine of the phase angle between current and voltage in the a.c. circuit.

Question 20.
State the laws of reflection.
Answer:

• The incident ray, reflected ray and normal to the reflecting surface all are coplanar (ie. lie in the same plane).
• The angle of incidence i is equal to the angle of reflection r. i = r

Question 21.
Why do metals have a large number of free electrons?
Answer:
In metals, the electrons in the outer most shells are loosely bound to the nucleus. Even at room temperature, there are a large number of free electrons which are moving inside the metal in a random manner.

Question 22.
The radius of the 5th orbit of hydrogen atom is 13.25 A. Calculate the wavelength of the electron in the 5th orbit.
Answer:
2πr = nλ
2 x 3.14 x 13.25 Å = 5 x λ
.’. λ = 16.64 Å

Question 23.
Draw the output waveform of a full wave rectifier.
Answer:

Question 24.
Explain centre frequency or resting frequency in frequency modulation.
Answer:
When the frequency of the baseband signal is zero (no input signal), there is no change in the frequency of the carrier wave. It is at its normal frequency and is called as centre frequency or resting frequency.

Part – III

Answer any six questions in which Q.No. 28 is compulsory. [6 x 3 = 18]

Question 25.
What is corona discharge?
Answer:
The electric field near the edge is very high and it ionizes the surrounding air. The positive ions are repelled at the sharp edge and negative ions are attracted towards the sharper edge.
This reduces the total charge of the conductor near the sharp edge. This is called action at points or corona discharge.

Question 26.
What is electric power and electric energy?
Answer:
Electric power: It is the rate at which an electric appliance converts electric energy into other forms of energy. Or, it is the rate at which work is done by a source of emf in maintaining an electric current through a circuit.
\({ P }=\frac { { W } }{ t } ={ VI }={ I }^{ 2 }{ R }=\frac { { V }^{ 2 } }{ { R } } \)
Electric energy: It is the total workdone in maintaining an electric current in an electric circuit for a given time.
W = Vt = VIr joule = I²R? joule.

Question 27.
A bar magnet having a magnetic moment \(\overrightarrow{\mathrm{M}}\) is cut into four pieces i.e., first cut in two pieces along the axis of the magnet and each piece is further cut into two pieces. Compute the magnetic moment of each piece.
Answer:
Consider a bar magnet of magnetic moment \(\overrightarrow{\mathrm{M}}\). When a bar magnet first cut in two pieces along the axis, their magnetic moment is \(\frac{\overrightarrow{\mathrm{M}}}{2}\)

Question 28.
The current in an inductive circuit is given by 0.3 sin (200t – 40°) A. Write the equation for the voltage across it if the inductance is 40 mH.
Answer:
L = 40 x 10^-3H; i = 0.1 sin (200 t – 40°); X_L = ωL = 200 x 40 x 10^-3 = 8 Ω
V_m = I_m X_L = 0.3 x 8 = 2.4 V
In an inductive circuit, the voltage leads the current by 90° Therefore,
υ = V_m sin (ωt + 90°)
υ = 2.4 sin (200f – 40°+ 90°)
υ = 2.4 sin (200f +50°)volt

Question 29.
Writedown the integral form of modified Ampere’s circuital law.
Answer:
This law relates the magnetic field around any closed path to the conduction current and displacement current through that path.

Question 30.
Two light sources have intensity of light as I_o. What is the resultant intensity at a point where the two light waves have a phase difference of π/3?
Answer:
Let the intensities be I_o
The resultant intensity is, I = 4 I_o cos² (φ/2)
Resultant intensity when, ϕ = π/ 3, is I = 4I₀ cos² (π / 6) I
= 4I₀(√3 / 2)² =3I₀

Question 31.
Write the properties of cathode rays.
Answer:

• Cathode rays possess energy and momentum and travel in a straight line with high speed of the order of 10⁷m s^-1
• It can be deflected by application of electric and magnetic fields.
• When the cathode rays are allowed to fall on matter, they produce heat.
• They affect the photographic plates and also produce fluorescence when they fall on   certain crystals and minerals.
• When the cathode rays fall on a material of high atomic weight, x-rays are produced.
• Cathode rays ionize the gas through which they pass.
• The speed of cathode rays is up \(\left( \frac { 1 }{ 10 } \right) ^{ th }\) of the speed of light.

Question 32.
Distinguish between wireline and wireless communication.
Answer:

Question 33.
What is the difference between Nano materials and Bulk materials?
Answer:

• The solids are made up of particles. Each of the particle has a definite number of atoms, which might differ from material to material. If the particle of a solid is of size less than 100 nm, it is said to be a ‘nano solid’.
• When the particle size exceeds 100 nm, it is a ‘bulk solid’. It is to be noted that nano and bulk solids may be of the same chemical composition.
• For example, ZnO can be both in bulk and nano form.
• Though chemical composition is the; same, nano form of the material shows strikingly different properties when compared to its bulk counterpart.

Part – IV

Answer all the questions.  [5 x 5 = 25]

Question 34.
(a) Calculate the electric field due to a dipole on its equatorial plane.
Answer:
Electric field due to an electric dipole at a point on the equatorial plane. Consider a point C at a distance r from the midpoint O of the dipole on the equatorial plane as shown in Figure.

Since the point C is equi­distant from +q and -q, the magnitude of the electric fields of +q and -q are the same. The direction of \(\overrightarrow{\mathrm{E}}_{+}\) is along BC \(\overrightarrow{\mathrm{E}}_{-} \) and the direction of E is along CA. \(\overrightarrow{\mathrm{E}}_{+} \) and \(\overrightarrow{\mathrm{E}}_{-} \) and E are resolved into two components; one component parallel to the dipole axis and the other perpendicular to it. The perpendicular components \(\left|\overrightarrow{\mathrm{E}}_{+}\right| \sin \theta \) and \(\left|\overrightarrow{\mathrm{E}}_{-}\right| \sin \theta \) are oppositely directed and cancel each other. The magnitude of the total electric field at point C is the sum of the parallel components of E₊ and E and its direction is \(\overrightarrow { { E } } _{ + }\quad and\quad \overrightarrow { { E } } _{ – }\) and its direction is along \(-\hat{p}\)

(b) How the emf of two cells are compared using potentiometer?
Answer:
Comparison of emf of two cells with a potentiometer: To compare the emf of two cells, the circuit connections are made as shown in figure. Potentiometer wire CD is connected to a battery Bf and a key K in series. This is the primary circuit. The end C of the wire is connected to the terminal M of a DPDT (Double Pole Double Throw) switch and the other terminal N is connected to a jockey through a galvanometer G and a high resistance HR. The cells whose emf ξ₁ and ξ₂ and to be compared are connected to the terminals M₁, N₁ and M₂, N₂, of the DPDT switch. The positive terminals of Bf ξ₁ and ξ₂ should be connected to the same end C.

The DPDT switch is pressed towards M₁, N₁ so that cell ξ₁, is included in the secondary circuit and the balancing length l₁, is found by adjusting the jockey for zero deflection. Then the second cells ξ₂, is included in the circuit and the balancing length l₂, is determined. Let r be the resistance per unit length of the potentiometer wire and I be the current flowing through the wire.
we have
ξ₁ = Irl₁ ……………….. (1)
ξ₂ = Irl₂ ……………….. (2)
By dividing equation (1) by (2)
\(\frac{\xi_{1}}{\xi_{2}}=\frac{l_{1}}{l_{2}}\)
By including a rheostat (Rh) in the primary circuit, the experiment can be repeated several times by changing the current flowing through it.

Question 35.
(a) Discuss the working of cyclotron in detail.
Answer:
Cyclotron : Cyclotron is a device used accelerate the charged particles to gain large kinetic energy. It is also called as high energy accelerator. It was invented by Lawrence and Livingston in 1934.

Principle : When a charged particle moves normal to the magnetic field, it experiences magnetic Lorentz force.

Construction : The particles are allowed to move in between two semicircular metal containers called Dees (hollow D – shaped objects). Dees are enclosed in an evacuated chamber and it is kept in a region with uniform magnetic field controlled by an electromagnet. The direction of magnetic field is normal to the plane of the are enclosed in an evacuated chamber and it is kept in a region with uniform magnetic field controlled by an electromagnet. The direction of magnetic field is normal to the plane of the Dees. The two Dees are kept separated with a gap and the source S (which ejects the particle to be accelerated) is placed at the center in the gap between the Dees. Dees are connected to high frequency alternating potential difference.

Working: Let us assume that the ion ejected from source S is positively charged. As soon as ion is ejected, it is accelerated towards a Dee (say, Dee – 1) which has negative potential at that time. Since the magnetic field is normal to the plane of the Dees, the ion undergoes circular path. After one semi-circular path in Dee-1, the ion reaches the gap between Dees. At this time, the polarities of the Dees are reversed so that the ion is now accelerated towards Dee-2 with a greater velocity. For this circular motion, the centripetal force of the charged particle q is provided by Lorentz force.

\(\frac { mv^{ 2 } }{ r } =qv{ B }\Rightarrow r=\frac { m }{ q{ B } } v\Rightarrow r\propto v\)
From the equation, the increase in velocity increases the radius of circular path. This process continues and hence the particle undergoes spiral path of increasing radius. Once it reaches near the Very important condition in cyclotron operation is the resonance condition. It happens when the frequency { at which the positive ion circulates in the magnetic field must be equal to the constant frequency of the electrical oscillator f_osc From equation
\(f_{\text {osc }}=\frac{q \mathrm{B}}{2 \pi m} \Rightarrow \mathrm{T}=\frac{1}{f_{\text {osc }}}\)
The time Period of oscillation is \(\mathrm{T}=\frac{2 \pi m}{q \mathrm{B}}\)
The kinetic energy of the charged particle is \(\mathrm{KE}=\frac{1}{2} m v^{2}=\frac{q^{2} \mathrm{B}^{2} r^{2}}{2 m}\)

Limitations of cyclotron

• the speed of the ion is limited
• electron cannot be accelerated
• uncharged particles cannot be accelerated

[OR]

(b) Give the uses of Foucault current.
Answer:
Though the production of eddy current is undesirable in some cases, it is useful in some other cases. A few of them are

(1) Induction stove : Induction stove is used to cook the food quickly and safely with less energy consumption. Below the cooking zone, there is a tightly wound coil of insulated wire. The cooking pan made of suitable material, is placed over the cooking zone. When the stove is switched on, an alternating current flowing in the coil produces high frequency alternating magnetic field which induces very strong eddy currents in the cooking pan. The eddy currents in the pan produce so much of heat due to Joule heating which is used to cook the food.

(2) Eddy current brake : This eddy current braking system is generally used in high speed trains and roller coasters. Strong electromagnets are fixed just above the rails. To stop the train, electromagnets are switched on. The magnetic field of these magnets induces eddy currents in the rails which oppose or resist the movement of the train. This is Eddy current linear brake.

In some cases, the circular disc, connected to the wheel of the train through a common shaft, is made to rotate in between the poles of an electromagnet. When there is a relative motion between the disc and the magnet, eddy currents are induced in the disc which stop the train. This is Eddy current circular brake.

(3) Eddy current testing : It is one of the simple non-destructive testing methods to find defects like surface cracks and air bubbles present in a specimen. A coil of insulated wire is given an alternating electric current so that it produces an alternating magnetic field. When this coil is brought near the test surface, eddy current is induced in the test surface. The presence of defects causes the change in phase and amplitude of the eddy current that can be detected by some other means. In this way, the defects present in the specimen are identified.

(4) Electro magnetic damping : The armature of the galvanometer coil is wound on a soft iron cylinder. Once the armature is deflected, the relative motion between the soft iron cylinder and the radial magnetic field induces eddy current in the cylinder. The damping force due to the flow of eddy current brings the armature to rest immediately and then galvanometer shows a steady deflection. This is called electromagnetic damping.

Question 36.
(a) Write down the properties of electromagnetic waves.
Answer:
Properties of electromagnetic waves:

• Electromagnetic waves are produced by any accelerated charge.
• Electromagnetic waves do not require any medium for propagation. So electromagnetic wave is a non-mechanical wave.
• Electromagnetic waves are transverse in nature. This means that the oscillating electric field vector, oscillating magnetic field vector and propagation vector (gives direction of propagation) are mutually perpendicular to each other.
• Electromagnetic waves travel with speed which is equal to the speed of light in vacuum
  or free space, \(c=\frac { 1 }{ \sqrt { \varepsilon _{ 0 }\mu _{ 0 } } } =3\times 10^{ 8 }{ ms }^{ -1 }\)
• The speed of electromagnetic wave is less than speed in free space or vacuum, that is, v < c. In a medium of refractive index,

[OR]

(b) Explain the Young’s double slit experimental setup and obtain the equation for path difference.
Answer:
Experimental setup
Wavefronts from S₁ and S₂ spread out and overlapping takes place to the right side of double slit. When a screen is placed at a distance of about 1 meter from the slits, alternate bright and dark fringes which are equally spaced appear on the screen. These are called interference fringes or bands.

S₁ and S₂ travel equal distances and arrive in-phase. These two waves constructively interfere and bright fringe is observed at O. This is called central bright fringe.

The fringes disappear and there is uniform illumination on the screen when one of the slits is covered. This shows clearly that the bands are due to interference.

Equation for path difference
Let d be the distance between the double slits S₁ and S₂ which act as coherent sources of wavelength λ. A screen is placed parallel to the double slit at a distance D from it. The mid-point of S₁ and S₂ is C and the midpoint of the screen O is equidistant from S₁ and S₂. P is any point at a distance y  from O.

The waves from S₁ and S₂ meet at P either inphase or out-of-phase depending upon the path difference between the two waves. The path difference S between the light waves from S₁ and S₂ to the point P is, δ = S₂P and S₁P
A perpendicular is dropped from the point S₁, to the line S₂P at M to find the path difference more precisely.
δ = S₂P – MP = S₂M
The angular position of the point P from C is θ. ∠OCP = θ.
From the geometry, the angles ∠OCP and ∠S₂S₁ M are equal.
∠OCP = ∠S₂S₁ M = θ
In right angle triangle ΔS₁S₂M, the path difference, S₂M = d sin θ
δ = d sin θ
If the angle θ is small, sin θ ≈ tan θ ≈ θ From the right angle triangle ΔOCP, tan θ = y/D. The path difference, δ =dy/D

Question  37.
(a) Give the construction and working of photo emissive cell.
Answer:
Photo emissive cell:
Its working depends on the electron emission from a metal cathode due to irradiation of light or other radiations.

• It consists of an evacuated glass or quartz bulb in which two metallic electrodes – that is, a cathode and an anode are fixed.
• The cathode C is semi-cylindrical in shape and is coated with a photo sensitive material. The anode A is a thin rod or wire kept along the axis of the semi-cylindrical cathode.
• A potential difference is applied between the anode and the cathode through a galvanometer G.

Working:

• When cathode is illuminated, electrons are emitted from it. These electrons are attracted by anode and hence a current is produced which is measured by the galvanometer
• For a given cathode, the magnitude of
  the current depends on the intensity to incident radiation and
  the potential difference between anode and cathode.

[OR]

Question 37.
(b) Explain the J.J. Thomson experiment to determine the specific charge of electron.
Answer:
In 1887, J. J. Thomson made remarkable improvement in the scope of study of gases in discharge tubes. In the presence of electric and magnetic fields, the cathode rays are deflected. By the variation of electric and magnetic fields, mass normalized charge or the specific charge (charge per unit mass) of the cathode rays is measured.

A highly evacuated discharge tube is used and cathode rays (electron beam) produced at cathode are attracted towards anode disc A. Anode disc is made with pin hole in order to allow only a narrow beam of cathode rays. These cathode rays are now allowed to pass through the parallel metal plates, maintained at high voltage. Further, this gas discharge tube is kept in between pole pieces of magnet such that both electric and magnetic fields are perpendicular to each other. When the cathode rays strike the screen, they produce scintillation and hence bright spot is observed. This is achieved by coating the screen with zinc sulphide.

(i) Determination of velocity of cathode rays
For a fixed electric field between the plates, the magnetic field is adjusted such that the cathode rays (electron beam) strike at the original position O. This means that the magnitude of electric force is balanced by the magnitude of force due to magnetic field. Let e be the charge of the cathode rays, then eE = eBv
\(v=\frac{E}{B}\) …………….. (1)

(ii) Determination of specific charge
Since the cathode rays (electron beam) are accelerated from cathode to anode, the potential energy of the electron beam at the cathode is converted into kinetic energy of the electron beam at the anode. Let V be the potential difference between anode and cathode, then the potential energy is eV. Then from law of conservation of energy,
\(e \mathrm{V}=\frac{1}{2} m v^{2} \Rightarrow \frac{e}{m}=\frac{v^{2}}{2 \mathrm{V}}\)
Substituting the value of velocity from equation (1) , we get
\(\frac{e}{m}=\frac{1}{2 \mathrm{V}} \frac{\mathrm{E}^{2}}{\mathrm{B}^{2}}\) ………..(2)
Substituting the value of E ,B and V, the specific charge vam be determined as
\(\frac{e}{m}=1.7 \times 10^{11} \mathrm{Ckg}^{-1}\)

(iii) Deflection of charge only due to uniform electric field
When the magnetic field is turned off, the deflection is only due to electric field. The
deflection in vertical direction is due to the electric force.
F_e = eE ………………….. (3)
Let m be the mass of the electron and by applying Newton’s second law of motion,
acceleration of the electron is
\(a_{e}=\frac{1}{m} \mathrm{F}_{e}\) ………………… (4)
Substituting equation (4) in equation (3),
\(a_{e}=\frac{1}{m} e E=\frac{e}{m} E\)
Let y be the deviation produced from original position on the screen. Let the initial upward velocity of cathode ray be μ = 0 before entering the parallel electric plates. Let l be the time taken by the cathode rays to travel in electric field. Let l be the length of one of the plates, then the time taken is
\(t=\frac{l}{v}\) …………(5)

Hence, the deflection y’ of cathod rays is( note : u = 0 and \(a_{e}=\frac{e}{m} \mathrm{E}\))

Therefore, the deflection y on the screen is
y α y’ ⇒ y = Cy’
where C is proportionality constant which depends on the geometry of the discharge tube and substituting y’ value in equation (6), we get

Substituting the values on RHS, the value of specific charge is calculated as
e/m = 1.7 x 10¹¹Ckg^-1

Question 38.
(a) What is an LED? Give the principle of operation with a diagram.
Answer:
Light Emitting Diode (LED): LED is a p-n junction diode which emits visible or invisible light when it is forward biased. Since, electrical energy is converted into light energy, this process is also called electroluminescence. The cross-sectional view of a commercial LED is shown in figure (b). It consists of a p-layer, n-layer and a substrate. A transparent window is used to allow light to travel in the desired direction. An external resistance in series with the biasing source is required to limit the forward current through the LED. In addition, it has two leads; anode and cathode.

When the p-n junction is forward biased, the conduction band electrons on n-side and valence band holes on p-side diffuse across the junction. When they cross the junction, they become excess minority carriers (electrons in p-side and holes in n-side). These excess minority carriers recombine with oppositely charged majority carriers in the respective regions, i.e. the. electrons in the conduction band recombine with holes in the valence band as shown in the figure (c). During recombination process, energy is released in the form of light (radiative) or heat (non-radiative). For radiative recombination, a photon of energy hv is emitted. For non- radiative recombination, energy is liberated in the form of heat.

The colour of the light is determined by the energy band gap of the material. Therefore, LEDs are available in a wide range of colours such as blue (SiC), green (AlGaP) and red (GaAsP). Now a days, LED which emits white light (GalnN) is also available.

[OR]

(b) Give the applications of ICT in mining and agriculture sectors.
Answer:
(i) Agriculture
The implementation of information and communication technology (ICT) in agriculture sector enhances the productivity, improves the living standards of farmers and overcomes the Challenges and risk factors.

• ICT is widely used in increasing food productivity and farm management.
• It helps to optimize the use of water, seeds and fertilizers etc.
• Sophisticated technologies that include robots, temperature and moisture sensors, aerial images, and GPS technology can be used.
• Geographic information systems are extensively used in farming to decide the suitable place for the species to be planted.

(ii) Mining

• ICT in mining improves operational efficiency, remote monitoring and disaster locating system.
• Information and communication technology provides audio-visual warning to the trapped underground miners.
• It helps to connect remote sites.

Students can Download Tamil Nadu 12th Biology Model Question Paper 2 English Medium Pdf, Tamil Nadu 12th Biology Model Question Papers helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

TN State Board 12th Biology Model Question Paper 2 English Medium

General Instructions:

1. 1. The question paper comprises of four parts. Questions for Botany and Zoology are asked separately.
   2. You are to attempt all the parts. An internal choice of questions is provided wherever applicable.
   3. All questions of Part I, II, III and IV are to be attempted separately.
   4. Question numbers 1 to 8 in Part I are Multiple Choice Questions of one mark each. These are to be answered by choosing the most suitable answer from the given four alternatives and writing the option code and the corresponding answer.
   5. Question numbers 9 to 14 in Part II are two-marks questions. These are to be answered in about one or two sentences.
   6. Question numbers 15 to 19 in Part III are three-marks questions. These are to be answered in about three to five short sentences.
   7. Question numbers 20 and 21 in Part IV are five-marks questions. These are to be answered in detail. Draw diagrams wherever necessary.

Time: 2.30 Hours
Maximum Marks: 70

Bio-Botany [Maximum Marks: 35]

Part – I

Choose the correct answer. [8 × 1 = 8]

Question 1.
How many different kinds of gametes will be produced by a plant having the genotype AABbCC?
(a) Three
(b) Four
(c) Nine
(d) Two
Answer:
(d) Two

Question 2.
pBR 322, BR stands for ________.
(a) Plasmid Bacterial Recombination
(b) Plasmid Bacterial Replication
(c) Plasmid Boliver and Rodriguez
(d) Plasmid Baltimore and Rodriguez
Answer:
(c) Plasmid Boliver and Rodriguez

Question 3.
Which of the given plant produces cardiac glycosides?
(a) Calotropis
(b) Acacia
(c) Nepenthes
(d) Utricularia
Answer:
(a) Calotropis

Question 4.
Methane is _______ times as effective as CO₂ at trapping heat.
(a) 5
(b) 10
(c) 20
(d) 100
Answer:
(c) 20

Question 5.
Statement 1: Arachis hypogea belongs to Fabaceae
Statement 2: It is a native of Brazil.
(a) Statement 1 is correct and Statement 2 is incorrect
(b) Statement 1 is incorrect and Statement 2 is correct
(c) Both the Statements are correct
(d) Both the Statements are incorrect
Answer:
(c) Both the Statements are correct

Question 6.
Which of the following scientist developed world’s first cotton hybrid?
(a) Dr. B.P. Pal
(b) C.T. Patel
(c) Dr. K. Ramiah
(d) N.G.P. Rao
Answer:
(b) C.T. Patel

Question 7.
Ecosystem is the structural and functional unit of ecology. This statement was given by _______.
(a) Tansley
(b) Odum
(c) Charles Elton
(d) Edwin
Answer:
(b) Odum

Question 8.
Name the scientist(s) who rediscovered the Mendelian work? .
(i) Hugo de Vries (ii) Carl Correns (iii) Tschermak (iv) T.H. Morgan
(a) (i), (ii)and (iv) (b) (i), (ii)and (iii) (iii) ii, iii, iv (d) i, iii and iv
Answer:
(b) (i), (ii)and (iii)

Part – II

Answer any four of the following questions. [4 × 2 = 8]

Question 9.
Detached leaf of Bryophyllum produces new plants. How?
Answer:
In Bryophyllum, the leaf is succulent and notched on its margin. Adventious buds develop at these notches and are called epiphyllous buds. They develop into new plants forming a root system and become independent plants when the leaf gets decayed.

Question 10.
Crossing over occurs only in germinal cells. Yes or No? Support your answer.
Answer:
No. Though crossing over is a common process in germinal cells rarely it also occurs in somatic cells during mitosis. Such crossing over is called mitotic crossing over or somatic crossing over.

Question 11.
Why do we use cryoprotectants in conservation process? Name any two cryoprotectant.
Answer:
Cryoprotectants are the protective agents that are used to protect the cells or tissues from the stress of freezing temperature. E.g: Sucrose, dimethyl sulphoxide.

Question 12.
What is Eltonian pyramid?
Answer:
Eltonian pyramid or Ecological pyramid is a graphic representation of the trophic structure and function at successive trophic levels of an ecosystem.

Question 13.
What do you understand by the term good ozone and bad ozone?
Answer:
The ozone layer of troposphere is called bad ozone.
The ozone layer of stratosphere is called good ozone because the layer acts as an shield for absorbing UV rays coming from sun which is harmful for living organisms causing ONA damage.

Question 14.
A person got irritation while applying chemical dye. What would be your suggestion for alternative?
Answer:
If a grey haired person is allergic on using chemical dyes then he can go for natural dyes like Henna. Henna is an organic dye obtained from leaves and young shoots of Lawsonia inermis. The principal colouring matter is Tacosone’ which is harmless and causes no irritation on skin.

Part – III

Answer any three questions in which question number 19 is compulsory. [3 × 3 = 9]

Question 15.
Differentiate between incomplete dominance and codominance.
Answer:
Incomplete Dominance:

• In incomplete dominance, neither of the allele is not completely dominant to another allele rather combine and produce new trait.
• New phenotype is formed due to character blending (not alleles)
• Example : Pink flowers of Mirabilis Jalapa

Co-dominance:

• In co-dominance, both the alleles in heterozygote are dominant and the traits are equally expressed (joint expression)
• No formation of new phenotype rather both dominant traits are expressed, conjointly.
• Example : Red and white flowers of camellia.

Question 16.
What are the features that a vector must possess to facilitate cloning?
Answer:
The following are the features that are required to facilitate cloning into a vector.

• Origin of replication (ori): This is a sequence from where replication starts and piece of DNA when linked to this sequence can be made to replicate within the host cells.
• Selectable marker: In addition to ori the vector requires a selectable marker, which helps in identifying and eliminating non-transformants and selectively permitting the growth of the transformants.
• Cloning sites: In order to link the alien DNA, the vector needs to have very few, preferably single, recognition sites for the commonly used restriction enzymes.

Question 17.
Define somatic embryogenesis? Give any two of its applications.
Answer:
Somatic embryogenesis is the formation of embryos from the callus tissue directly and these embryos are called Embryoids.

Applications:

• Somatic embryogenesis provides potential plantlets which after hardening period can establish into plants.
• Somatic embryoids can be used for the production of synthetic seeds.

Question 18.
What is TSM? How it is classified and what does it focuses on?
Answer:
TSM stands for Traditional Systems of Medicines India has a rich medicinal heritage. A number of Traditional Systems of Medicine (TSM) are practiced in India some of which come from outside India. TSM in India can be broadly classified into institutionalized or documented and non-institutionalized or oral traditions. Institutionalized Indian systems include Siddha and Ayurveda which are practiced for about two thousand years.

These systems have prescribed texts in which the symptoms, disease diagnosis, drugs to cure, preparation of drugs, dosage and diet regimes, daily and seasonal regimens. Non-institutional systems, whereas, do not have such records and or practiced by rural and tribal peoples across India. The knowledge is mostly held in oral form. The TSM focus on healthy lifestyle and healthy diet for maintaining good health and disease reversal

Question 19.
How do sacred groves help in the conservation of biodiversity?
Answer:
These are the patches or grove of cultivated trees which are community protected and are based on strong religious belief systems which usually have a significant religious connotation for protecting community. Each grove is an abode of a deity mostly village God Or Goddesses like Aiyanar or Amman. 448 grooves were documented throughout Tamil Nadu, of which 6 groves (Banagudi shola, Thirukurungudi and Udaiyankudikadu, Sittannnavasal, Puthupet and Devadanam) were taken up for detailed floristic and faunistic studies.

These groves provide a number of ecosystem services to the neighbourhood like protecting watershed, fodder, medicinal plants and micro climate control.

Part – IV

Answer all the questions. [2 × 5 = 10]

Question 20.
(a) Draw a flow chart depicting the various types of ploidy.
Answer:

[OR]

(b) Mention the application of biotechnology.
Answer:

• Biotechnology is one of the most important applied interdisciplinary sciences of the 21st century. It is the trusted area that enables us to find the beneficial way of life.
• Biotechnology has wide applications in various sectors like agriculture, medicine, environment and commercial industries.
• This science has an invaluable outcome like transgenic varieties of plants e.g. transgenic cotton (Bt-cotton), rice, tomato, tobacco, cauliflower, potato and banana.
• The development of transgenics as pesticide resistant, stress resistant and disease resistant varieties of agricultural crops is the immense outcome of biotechnology.
• The synthesis of human insulin and blood protein in E.coli and utilized for insulin deficiency disorder in human is a breakthrough in biotech industries in medicine.
• The synthesis of vaccines, enzymes, antibiotics, dairy products and beverages are the products of biotech industries.
• Biochip based biological computer is one of the successes of biotechnology.
• Genetic engineering involves genetic manipulation, tissue culture involves aseptic cultivation of totipotent plant cell into plant clones under controlled atmospheric conditions.
• Single cell protein from Spirulina is utilized in food industries.
• Production of secondary metabolites, biofertilizers, biopesticides and enzymes.
• Biomass energy, biofuel, bioremediation and phytoremediation for environmental biotechnology.

Question 21.
(a) Differentiate Primary succession and Secondary succession.
Answer:
Primary succession:

• Developing in an barren area.
• Initiated due to a biological or any other external factors.
• No soil, while primary succession starts
• Pioneer species come from outside environment.
• It takes more time to complete.

Secondary succession:

• Developing in disturbed area.
• Starts due to external factors only.
• It starts where soil covers is already present.
• Pioneer species develop from existing environment.
• It takes comparatively less time to complete.

(b) Enumerate the characters of anemophilous flowers
Answer:
Anemophilous plants have the following characteristic features:

• The flowers are produced in pendulous, catkin-like or spike inflorescence.
• The axis of inflorescence elongates so that the flowers are brought well above the leaves.
• The perianth is absent or highly reduced.
• The flowers are small, inconspicuous, colourless, not scented, do not secrete nectar.
• The stamens are numerous, filaments are long, exerted and versatile.
• Anthers produce enormous quantities of pollen grains compared to number of ovules available for pollination. They are minute, light and dry so that they can be carried to long distances by wind.
• In some plants anthers burst violently and release the pollen into the air. Example: Urtica.
• Stigmas are comparatively large, protruding, sometimes branched and feathery, adapted to catch the pollen grains. Generally single ovule is present.
• Plant produces flowers before the new leaves appear, so the pollen can be carried without hindrance of leaves.

Bio-Zoology [Maximum Marks: 35]

Part – I

Choose the correct answer. [8 × 1 = 8]

Question 1.
Which one of the following groups includes sexually transmitted diseases caused by bacteria only?
(a) Syphilis, gonorrhoea and candidiasis
(b) Syphilis, chlamydiasis and gonorrhoea
(c) Syphilis, gonorrhoea and trichomoniasis
(d) Syphilis, trichomoniasis and pediculosis
Answer:
(b) Syphilis, chlamydiasis and gonorrhoea

Question 2.
ABO blood group in man is controlled by __________.
(a) Multiple alleles
(b) Lethal genes
(c) Sex linked genes
(d) Y-linked genes
Answer:
(a) Multiple alleles

Question 3.
Hershey and Chase experiment with bacteriophage showed that ____________.
(a) Protein gets into the bacterial cells
(b) DNA is the genetic material
(c) DNA contains radioactive sulphur
(d) Viruses undergo transformation
Answer:
(b) DNA is the genetic material

Question 4.
Modern man belongs to which period?
(a) Quaternary
(b) Cretaceous
(c) Silurian
(d) Cambrian
Answer:
(a) Quaternary

Question 5.
Allergy involves _______.
(a) IgE
(b) IgG
(c) IgA
(d) IgM
Answer:
(a) IgE

Question 6.
Recombinant Factor VIII is produced in the ______ of the Chinese Hamster.
(a) Liver cells
(b) blood cells
(c) ovarian cells
(d) brain cells
Answer:
(c) ovarian cells

Question 7.
Match with correct pair

(a) A – ii, B – iv, C – i, D – iii
(b) A – ii, B – iii, C – i, D – iv
(d) A – iii, B – i, C – iv, D – ii
(d) A – iv, B – ii, C – i, D – iii
Answer:
(b) A – ii, B – iii, C – i, D – iv

Question 8.
Assertion (A): Snake is a stenotherm.
Reason (R): Organism can tolerate narrow temperature fluctuations.
(a) Both A and R are correct R explain A
(b) A is correct R is incorrect
(c) A and R are correct, R doesn’t explains A
(d) Both A and R are incorrect
Answer:
(a) Both A and R are correct R explain A

PART – II

Answer any four of the following questions. [4 × 2 = 8]

Question 9.
Mention the differences between spermiogenesis and spermatogenesis.
Answer:
Spermiogenesis:
Transformation of spermatids into mature sperm.

Spermatogenesis:
Spermatogenesis is the sequence of events in the seminiferous tubules of testes that produces male gametes, the sperms.

Question 10.
Draw and label a gemmule of sponge.
Answer:

Question 11.
State Wiener’s Hypothesis on Rh-factor.
Answer:
Wiener proposed the existence of eight alleles (R¹, R², R⁰, R^Z, r, r¹, r¹¹, r^y) at a single Rh locus. All genotypes carrying a dominant ‘R allele’ (R¹, R², R⁰, R^z) will produce ‘Rh-positive’ phenotype and double recessive genotypes (rr, rr¹, rr¹¹, rr^y) will give rise to Rh-negative phenotype.

Question 12.
Why t-RNA is called an adapter molecule?
Answer:
The transfer RNA (t-RNA) molecule of a cell acts as a vehicle that picks up the amino acids scattered through the cytoplasm and also reads specific codes of mRNA molecules. Hence it is called as adapter molecule. This term was postulated by Francis Crick.

Question 13.
Why Red list is prepared periodically?
Answer:
The purpose of preparation of Red List are:

• To create awareness on the degree of threat to biodiversity
• Identification and documentation of species at high risk of extinction
• Provide global index on declining biodiversity .
• Preparing conservation priorities and help in conservation of action
• Information on international agreements on conservation of biological diversity

Question 14.
Write notes on (a) Eutrophication (b) Algal Bloom
Answer:
Eutrophication refers to the nutrient enrichment in water bodies leading to lack of oxygen and will end up in the death of aquatic organisms.
Algal Bloom is an excess growth of algae due to abundant excess nutrients imparting distinct color to water.

Part – III

Answer any three questions in which question number 19 is compulsory. [3 × 3 = 9]

Question 15.
Explain Foetal-ejection reflex.
Answer:
As the pregnancy progresses, increase in the oestrogen concentration promotes uterine contractions. These uterine contractions facilitate moulding of the foetus and downward movement of the foetus. The descent of the foetus causes dilation of cervix of the uterus and vaginal canal resulting in a neurohumoral reflex called Foetal ejection reflex or Ferguson reflex.

This initiates the secretion of oxytocin from the neurohypophysis which in turn brings about the powerful contraction of the uterine muscles and leads to the expulsion of the baby through the birth canal.

Question 16.
Role of Y- chromosome is crucial for maleness – Justify.
Answer:
Current analysis of Y chromosomes has revealed numerous genes and regions with potential genetic function; some genes with or without homologous counterparts are seen on the X. Present at both ends of the Y chromosome are the pseudoautosomal regions (PARs) that are similar with regions on the X chromosome which synapse and recombine during meiosis. The remaining 95% of the Y chromosome is referred as the Non-combining Region of the Y (NRY).

The NRY is divided equally into functional genes (euchromatic) and non-functional genes (heterochromatic). Within the euchromatin regions, is a gene called Sex determining region Y (SRY). In humans, absence of Y chromosome inevitably leads to female development and this SRY gene is absent in X chromosome. The gene product of SRY is the testes determining factor (TDF) present in the adult male testis.

Question 17.
State immunological surveillance theory.
Answer:
The concept of immunological surveillance postulates that the primary function of the immune system is to “seek and destroy” malignant cells that arise by somatic mutation. The efficiency of the surveillance mechanism reduces either as a result of ageing or due to congenital or acquired immuno deficiencies, leads to increased incidence of cancer. Thus, if immunological surveillance is effective, cancer should not occur. The development of tumour represents a lapse in surveillance.

Question 18.
Write a short note on Pathaneer.
Answer:
In some parts of South India, a traditional drink called pathaneer is obtained from fermenting sap of palms and coconut trees. A common source is tapping of unopened spadices of coconut. It is a refreshing drink, which on boiling produces jaggery or palm sugar. When pathaneer is left undisturbed for few hours it gets fermented to form toddy with the help of naturally occurring yeast, to form a beverage that contains 4 percent alcohol. After 24 hours toddy becomes unpalatable and is used for the production of vinegar.

Question 19.
Elucidate the methodology of ELISA test.
Answer:
During diagnosis the sample suspected to contain the antigen is immobilized on the surface of an ELISA plate. The antibody specific to this antigen is added and allowed to react with the immobilized antigen. The anti-antibody is linked to an appropriate enzyme like peroxidase.

The unreacted anti-antibody is washed away and the substrate of the enzyme (hydrogen peroxidase) is added with certain reagents such as 4-chloronaphthol. The activity of the enzyme yields a coloured product indicating the presence of the antigen.

Part – IV

Answer all the questions. [2 × 5 = 10]

Question 20.
(a) What are IUD’s? Explain its way of functioning. Also describe their types.
Answer:
Intrauterine Devices (IUDs) are inserted by medical experts in the uterus through the vagina. These devices are available as copper releasing IUDs, hormone releasing IUDs and nonmedicated IUDs. IUDs increase phagocytosis of sperm within the uterus. IUDs are the ideal contraceptives for females who want to delay pregnancy. It is one of the popular methods of contraception in India and has a success rate of 95 to 99%.

Copper releasing IUDs differ from each other by the amount of copper. Copper IUDs such as Cu T-380 A, Nova T, Cu 7, Cu T 380 Ag, Multiload 375, etc. release free copper and copper salts into the uterus and suppress sperm motility. They can remain in the uterus for five to ten years.

Hormone-releasing IUDs such as Progestasert and LNG – 20 are often called as intrauterine systems (IUS). They increase the viscosity of the cervical mucus and thereby prevent sperms from entering the cervix.

Non-medicated IUDs are made of plastic or stainless steel. Lippes loop is a double S-shaped plastic device.

[OR]

(b) Explain how Urey – Miller’s experiment supports the origin of life?
Answer:

Urey and Miller (1953), paved way for understanding the possible synthesis of organic compounds that led to the appearance of living organisms is depicted in the Figure In their experiment, a mixture of gases was allowed to circulate over electric discharge from an tungsten electrode.

A small flask was kept boiling and the steam emanating from it was made to mix with the mixture of gases (ammonia, methane and hydrogen) in the large chamber that was connected to the boiling water. The steam condensed to form water which ran down the ‘U’ Diagrammatic representation of Urey-Miller’s experiment tube. Experiment was conducted continuously for a week and the liquid was analysed. Glycine, alanine, beta alanine and aspartic acid were identified.

Thus Miller’s experiments had an insight as to the possibility of abiogenetic synthesis of large amount of variety of organic compounds in nature from a mixture of sample gases in which the only source of carbon was methane. Later in similar experiments, formation of all types of amino acids, and nitrogen bases were noticed.

Question 21.
(a) Discuss any two Allosomal abnormalities in human beings.
Answer:
Allosomal abnormalities in human beings:
Mitotic or meiotic non-disjunction of sex chromosomes causes allosomal abnormalities.
Several sex chromosomal abnormalities have been detected. E.g. Klinefelter’s syndrome and
Turner’s syndrome.

1. Klinefelter’s Syndrome (XXY Males):
This genetic disorder is due to the presence of an additional copy of the X chromosome resulting in a karyotype of 47, XXY. Persons with this syndrome have 47 chromosomes (44AA+XXY). They are usually sterile males, tall, obese, with long limbs, high pitched voice, under developed genetalia and have feeble breast (gynaecomastia) development.

2. Turner’s Syndrome (XO Females):
This genetic disorder is due to the loss of a X chromosome resulting in a karyotype of 45 ,X. Persons with this syndrome have 45 chromosomes (44 autosomes and one X chromosome) (44AA+XO) and are sterile females. Low stature, webbed neck, under developed breast, rudimentary gonads lack of menstrual cycle during puberty, are the main symptoms of this syndrome:

[OR]

(b) Explain in detail about various types of extinctions.
Answer:
There are three types of Extinctions
1. Natural extinction: It is a slow process of replacement of existing species with better adapted species due to changes in environmental conditions, evolutionary changes, predators and diseases. A small population can get extinct sooner than the large population due to inbreeding depression (less adaptivity and variation)

2. Mass extinction: The Earth has experienced quite a few mass extinctions due to environmental catastrophes. A mass extinction occurred about 225 million years ago during the Permian, where 90% of shallow water marine invertebrates disappeared.

3. Anthropogenic extinctions: These are abetted by human activities like hunting, habitat destruction, over exploitation, urbanization and industrialization. Some examples of extinctions are Dodo of Mauritius and Steller’s sea cow of Russia. Amphibians seem to be at higher risk of extinction because of habitat destruction.

The most serious aspect of the loss of biodiversity is the extinction of species. The unique information contained in its genetic material (DNA) and the niche it possesses are lost forever.

Students can Download Tamil Nadu 12th Maths Model Question Paper 3 English Medium Pdf, Tamil Nadu 12th Maths Model Question Papers helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

TN State Board 12th Maths Model Question Paper 3 English Medium

Instructions:

1.  The question paper comprises of four parts.
2.  You are to attempt all the parts. An internal choice of questions is provided wherever applicable.
3. questions of Part I, II. III and IV are to be attempted separately
4. Question numbers 1 to 20 in Part I are objective type questions of one -mark each. These are to be answered by choosing the most suitable answer from the given four alternatives and writing the option code and the corresponding answer
5. Question numbers 21 to 30 in Part II are two-marks questions. These are to be answered in about one or two sentences.
6. Question numbers 31 to 40 in Parr III are three-marks questions, These are to be answered in about three to five short sentences.
7. Question numbers 41 to 47 in Part IV are five-marks questions. These are to be answered) in detail. Draw diagrams wherever necessary.

Time: 3 Hours
Maximum Marks: 90

Part – I

I. Choose the correct answer. Answer all the questions. [20 × 1 = 20]

Question 1.
If A is a 3 × 3 non-singular matrix such that AA^T = A^T A and B = A^-1 A^T, then BB^T = ________.
(a) A
(b) B
(c) I₃
(d) B^T
Answer:
(c) I₃

Question 2.
The rank of the matrix \(\left[\begin{array}{cc}
7 & -1 \\
2 & 1
\end{array}\right]\) is ________.
(a) 9
(b) 2
(c) 1
(d) 5
Answer:
(b) 2

Question 3.
The value of \(\sum_{i=1}^{13}\left(i^{n}+i^{n-1}\right)\) is ________.
(a) 1 + i
(b) i
(c) 1
(d) 0
Answer:
(a) 1 + i

Question 4.
Which of the following is incorrect?
(d) Re(z) ≤ |z|
(b) Im (z) ≤ |z|
(c) \(z \bar{z}=|z|^{2}\)
(d) Re(z) ≥ |z|
Answer:
(d) Re(z) ≥ |z|

Question 5.
According to the rational root theorem, which number is not possible rational zero of 4x⁷ + 2x⁴ – 10x³ – 5?
(a) -1
(b) \(\frac{5}{4}\)
(c) \(\frac{4}{5}\)
(d)5
Answer:
(c) \(\frac{4}{5}\)

Question 6.
If \(\cot ^{-1}(\sqrt{\sin \alpha})+\tan ^{-1}(\sqrt{\sin \alpha})=u\), then cos 2u is equal to ______.
(a) tan² α
(b) o
(c) -1
(d) tan 2α
Answer:
(c) -1

Question 7.
The domain of the function defined by f(x) = sin^-1 \(\sqrt{x-1}\) is _______.
(a) [1, 2]
(b) [-1, 1]
(c) [0, 1]
(d) [-1, 0]
Answer:
(a) [1, 2]

Question 8.
The area of quadrilateral formed with foci of the hyperbolas \(\frac{x^{2}}{a^{2}}-\frac{y^{2}}{b^{2}}=1\) and \(\frac{x^{2}}{a^{2}}-\frac{y^{2}}{b^{2}}=-1\) is ________.
(a) 4(a² + b²)
(b) 2(a² + b²)
(c) a² + b²
(d) \(\frac{1}{2}\) (a² + b²)
Answer:
(b) 2(a² + b²)

Question 9.
The directrix of the parabola x² = -4y is ________.
(a) x = 1
(b) x = 0
(c) y = 1
(d) y = 0
Answer:
(c) y = 1

Question 10.
If the line \(\frac{x-2}{3}=\frac{y-1}{-5}=\frac{z+2}{2}\) lies in the plane x + 3y – αz + b = β, then (α, β) is ______
(a) (-5, 5)
(b) (-6, 7)
(c) (5, -5)
(d) (6, -7)
Answer:
(b) (-6, 7)

Question 11.
If \(\vec{a} \times(\vec{b} \times \vec{c})=(\vec{a} \times \vec{b}) \times \vec{c}\) for non-coplanar vectors \(\vec{a}, \vec{b}, \vec{c}\) then ________.
(a) \(\vec{a}\) parallel to \(\vec{b}\)
(b) \(\vec{b}\) parallel to \(\vec{c}\)
(c) \(\vec{c}\) parallel to \(\vec{a}\)
(d) \(\vec{a}+\vec{b}+\vec{c}=\overrightarrow{0}\)
Answer:
(c) \(\vec{c}\) parallel to \(\vec{a}\)

Question 12.
The maximum product of two positive numbers, when their sum of the squares is 200, is ________.
(a) 100
(b) \(25 \sqrt{7}\)
(c) 28
(d) \(24 \sqrt{14}\)
Answer:
(a) 100

Question 13.
If w(x,y, z) = x² (y – z) + y² (z – x) + z² (x – y), then \(\frac{\partial w}{\partial x}+\frac{\partial w}{\partial y}+\frac{\partial w}{\partial z}\) is ________.
(a) xy + yz + zx
(b) x (y + z)
(c) y (z + x)
(d) 0
Answer:
(d) 0

Question 14.
If u (x, y) = x² + 3xy + y – 2019, then \(\left.\frac{\partial u}{\partial x}\right|_{(4,-5)}\) is equal to ______.
(a) -4
(b) -3
(c) -7
(d) 13
Answer:
(c) -7

Question 15.
The volume of solid of revolution of the region bounded by y² = x (a – x) about x-axis is ________.

Answer:
(d) \(\frac{\pi a^{3}}{6}\)

Question 16.
\(\int_{0}^{a} f(x) d x+\int_{0}^{a} f(2 a-x) d x\) = _________.

Answer:
(c) \(\int_{0}^{2 a} f(x) d x\)

Question 17.
The differential equation of the family of curves y = Ae^x + Be^-x, where A and B are arbitrary constants is _______.

Answer:
(b) \(\frac{d^{2} y}{d x^{2}}-y=0\)

Question 18.
The differential equation corresponding to xy = c² where c is an arbitrary constant, is ______.
(a) xy”+ x = 0
(b) y” = 0
(c) xy’ + y = 0
(d) xy”- x = 0
Answer:
(c) xy’ + y = 0

Question 19.
If \(f(x)=\left\{\begin{array}{ll}
2 x, & 0 \leq x \leq a \\
0 & , \text { otherwise }
\end{array}\right.\)
is a probability density function of a random variable, then the value of a is _________.
(a) 1
(b) 2
(c) 3
(d) 4
Answer:
(a) 1

Question 20.
The proposition \(p \wedge(\neg p \vee q)\) is
(a) a tautology
(b) a contradiction
(c) logically equivalent to p ∧ q
(d) logically equivalent to p ∨ q
Answer:
(c) logically equivalent to p ∧ q

Part – II

II. Answer any seven questions. Question No. 30 is compulsory. [7 × 2 = 14]

Question 21.
A 12 metre tall tree was broken into two parts. It was found that the height of the part which was left standing was the cube root of the length of the part that was cut away. Formulate this into a mathematical problem to find the height of the part which was cut away.
Answer:
Let the two parts be x and (12 – x)
Given that x = \(\sqrt[3]{12-x}\)
Cubing on both side, x³ = 12 – x
x³ + x – 12 = 0

Question 22.
Find the value of \(\sin ^{-1}\left(\sin \frac{5 \pi}{9} \cos \frac{\pi}{9}+\cos \frac{5 \pi}{9} \sin \frac{\pi}{9}\right)\)
Answer:

Question 23.
Obtain the equation of the circles with radius 5 cm and touching x-axis at the origin in general form.
Answer:

Given radius = 5 cm and the circle is touching x axis
So centre will be (0, ± 5) and radius = 5
The equation of the circle with centre (0, ± 5) and radius 5 units is
(x – 0)² + (y ± 5)² = 5²
(i.e) x² + y² ± 10y + 25 – 25 = 0
(i.e) x² + y² ± 10y = 0

Question 24.
Find the length of the perpendicular from the origin to the plane.
\(\bar{r} \cdot(3 \vec{i}+4 \bar{j}+12 \vec{k})=26\).
Answer:
Taking the equation of the plane in cartesian form we get,
\((x \vec{i}+y \vec{j}+z \vec{k}) \cdot(3 \vec{i}+4 \vec{j}+12 \vec{k})=26\)
i.e. 3x + 4y + 12z – 26 = 0
The length of the perpendicular from (0, 0, 0) to the above plane is

Question 25.
Evaluate \(\lim _{x \rightarrow \pi / 2} \frac{\log (\sin x)}{(\pi-2 x)^{2}}\)
Answer:

Note that here l’ Hospitals rule, applied twice yields the result.

Question 26.
Evaluate \(\int_{-1}^{1} e^{-\lambda x}\left(1-x^{2}\right) d x\)
Answer:
Taking u = 1 – x² and v= e^-λx, and applying the Bernoulli’s formula, we get

Question 27.
Solve: \(\frac{d y}{d x}+2 y=e^{-x}\)
Answer:
Given that \(\frac{d y}{d x}+2 y=e^{-x}\)
This is a linear differential equation.
Here P = 2; Q = e
∫P dx = ∫2 dx = 2x
Thus, I.F = e^∫Pdx = e^2x
Hence the solution of (1) is \(y e^{\int \mathrm{P} d x}=\int \mathrm{Q} e^{\int \mathrm{P} d x} d x+c\)
That is, ye^2x = ∫e^-x e^2x dx + c (or) ye^2x = e^x + c (or) y = e^-x + ce^-2x is the required solution.

Question 28.
Three fair coins are tossed simultaneously. Find the probability mass function for number of heads occurred.
Answer:
When three coins are tossed, the sample space is
S = {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}
‘X’ is the random variable denotes the number of heads.
∴ ‘X’ can take the values of 0, 1, 2 and 3
Hence, the probabilities
P(X = 0) = P (No heads) = \(\frac{1}{8}\);
P(X = 1) = P (1 head) = \(\frac{3}{8}\);
P(X = 2) = P (2 heads) = \(\frac{3}{8}\);
P(X = 3) = P (3 heads)= \(\frac{1}{8}\);
∴ The probability mass function is
\(f(x)=\left\{\begin{array}{lll}
1 / 8 & \text { for } & x=0,3 \\
3 / 8 & \text { for } & x=1,2
\end{array}\right.\)

Question 29.
Construct the truth table for \((p \vee q) \vee \neg q\)
Answer:
truth table for \((p \vee q) \vee \neg q\)

Question 30.
Show that f(x, y) = \(\frac{x^{2}-y^{2}}{y^{2}+1}\) is continuous at every (x, y) ∈ R².
Answer:

Here, f satisfies all the three conditions of continuity at (a, b). Hence, f is continuous at every point of R² as (a, b) ∈ R².

Part – III

III. Answer any seven questions. Question No. 40 is compulsory. [7 × 3 = 21]

Question 31.
Form a polynomial equation with integer coefficients with \(\sqrt{\frac{\sqrt{2}}{\sqrt{3}}}\) as a root.

Question 32.
Find the equation of the tangents from the point (2, -3) to the parabola y² = 4x

Question 33.
Find the vector and cartesian equations of the straight line passing through the points (-5, 2, 3) and (4,-3, 6).

Question 34.
Find the points on the curve y = x³ – 6x² + x + 3 where the normal is parallel to the line x + y =1729.

Question 35.
Assuming log₁₀ e = 0.4343, find an approximate value of log₁₀ 1003.

Question 36.
Evaluate: \(\int_{0}^{\frac{\pi}{2}} \sin ^{2} x \cos ^{4} x d x\)

Question 37.
Solve the differential equation: \(\frac{d y}{d x}\) = e^x+y + x³ e^y

Question 38.
Using binomial distribution find the mean and variance of X for the following experiments
(i) A fair coin is tossed 100 times, and X denote the number of heads.
(ii) A fair die is tossed 240 times, and X denote the number of times that four appeared.

Question 39.
Let

be any three Boolean matrices of the same type. Find (A ∨ B) ∧C

Question 40.
Sketch the graph of y = sin\(\left(\frac{1}{3} x\right)\) for 0 ≤ x < 6π.

Part – IV

IV. Answer all the questions. [7 × 5 = 35]

Question 41.
(a) A fish tank can be filled in 10 minutes using both pumps A and B simultaneously. However, pump B can pump water in or out at the same rate. If pump B is inadvertently run in reverse, then the tank will be filled in 30 minutes. How long would it take each pump to fill the tank by itself ? (Use Cramer’s rule to solve the problem).
[OR]
(b) Using elementary transformations find the inverse of the matrix \(\left[\begin{array}{ccc}
1 & 3 & -2 \\
-3 & 0 & -5 \\
2 & 5 & 0
\end{array}\right]\)

Question 42.
42. (a) Let z₁, z₂, and z₃ be complex numbers such that |z₁| = |z₂| = |z₃| = r > 0 and z₁ +z₂ + z₃ ≠ 0.
Prove that \(\left|\frac{z_{1} z_{2}+z_{2} z_{3}+z_{3} z_{1}}{z_{1}+z_{2}+z_{3}}\right|=r\)
[OR]
(b) Find all cube roots of \(\sqrt{3}\) + i.

Question 43.
(a) Find all zeros of the polynomial x⁶ – 3x⁵ – 5x⁴ + 22x³ – 39x² – 39x + 135, if it is known that 1 + 2i and \(\sqrt{3}\) are two of its zeros.
[OR]
(b) Let W(x, y, z) = x² – xy + 3 sin z, x, y, z∈R. Find the linear approximation at (2, -1, 0)

Question 44.
(a) Prove p → (q → r) ≡ (p ∧ q) → r without using truth table.
[OR]
(b) Evaluate \(\int_{0}^{\frac{\pi}{4}} \frac{1}{\sin x+\cos x} d x\)

Question 45.
(a) Prove that \(\text { (i) } \tan ^{-1} \frac{2}{11}+\tan ^{-1} \frac{7}{24}=\tan ^{-1} \frac{1}{2} \text { (ii) } \sin ^{-1} \frac{3}{5}-\cos ^{-1} \frac{12}{13}=\sin ^{-1} \frac{16}{65}\)
[OR]
(b) Find two positive numbers whose product is 100 and whose sum is minimum.

Question 46.
(a) If X is the random variable with distribution function F (x) given by,
\(\mathrm{F}(x)=\left\{\begin{array}{ll}
0, & x<0 \\
\frac{1}{2}\left(x^{2}+x\right) & 0 \leq x<1 \\
1, & x \geq 1
\end{array}\right.\)
then find (i) the probability density function f(x) (ii) P(0.3 ≤ X ≤ 0.6)
[OR]
(b) Find the vertex, focus, equation of directrix and length of the latus rectum of the following: y² – 4y – 8x + 12 = 0

Question 47.
(a) The rate at which the population of a city increases at any time is proportional to the population at that time. If there were 1,30,000 people in the city in 1960 and 1,60,000 in 1990, what population may be anticipated in 2020? [log_e \(\left(\frac{16}{3}\right)\) = 0.2070; e^-0.42 = 1.52]
[OR]
(b) Find the parametric vector, non-parametric vector and Cartesian form of the equation of the plane passing through the point (3, 6, -2), (-1, -2, 6) and (6, 4, -2).

Students can Download Tamil Nadu 12th Physics Model Question Paper 3 English Medium Pdf, Tamil Nadu 12th Physics Model Question Papers helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

TN State Board 12th Physics Model Question Paper 3 English Medium

General Instructions:

• The question paper comprises of four parts.
• You are to attempt all the parts. An internal choice of questions is provided wherever applicable.
• All questions of Part I, II, III, and IV are to be attempted separately.
• Question numbers 1 to 15 in Part I are Multiple Choice Questions of one mark each.
  These are to be answered by choosing the most suitable answer from the given four
  alternatives and writing the option code and the corresponding answer
• Question numbers 16 to 24 in Part II are two-mark questions. These are to be answered
  in about one or two sentences.
• Question numbers 25 to 33 in Part III are three-mark questions. These are to be answered
  in about three to five short sentences.
• Question numbers 34 to 38 in Part IV are five-mark questions. These are to be answered
  in detaiL Draw diagrams wherever necessary.

Time: 3 Hours
Max Marks: 70

Part – I

Answer all the questions. Choose the correct answer. [15 x 1 = 15]

Question 1.
A thin conducting spherical shell of radius R has a charge Q which is uniformly distributed on its surface. the correct plot for electrostatic potential due to this spherical shell is ………

Answer:
(b)

Question 2.
The temperature coefficient of resistance of a wire is 0.00125 per °C. At 300 K, its resistance is 1Ω. The resistance of the wire will be 2Ω at …………….
(a) 1154 K
(b) 1100 K
(c) 1400K
(d) 1127 K
Answer:

Question 3.
n resistances, each of r Ω, when connected in parallel give an equivalent resistance of R Ω. If these resistances were connected in series, the combination would have a resistance in horns equal to ………..
(a) n²R
(b) \(\frac{R}{n^{2}}\)
(c) \(\frac{R}{n}\)
(d) nR
Answer:
(a) n²R
Hint :
Resistance in parallel combination, R= r/n = r = Rn
Resistance in series combination , R = nr = n²R

Question 4.
A thin insulated wire forms a plane spiral of N = 100 tight turns carrying a current 1 = 8 m A (milli ampere). The radii of inside and outside turns are a = 50 mm and b = 100 mm respectively. The magnetic induction at the center of the spiral is……………………….
(a) 5 μT
(b) 7 μT
(c) 8 μT
(d) 10 μT
Answer:
(b) 7 μT

Question 5.
In an oscillating LC circuit, the maximum charge on the capacitor is Q. The charge on the capacitor, when the energy is stored equally between the electric and magnetic fields, is……………………….
(a) \(\frac{Q}{2} \)
(b) \(\frac{Q}{\sqrt{3}}\)
(c) \(\frac{Q}{\sqrt{2}}\)
(d) Q
Answer:
(c) \(\frac{Q}{\sqrt{2}}\)

Question 6.
The direction of induced current during electro magnetic induction is given by …………………………………..
(a) Faraday’s law
(b) Lenz’s law
(c) Maxwell’s law
(d)  Ampere’s law
Answer:
(b) Lenz’s law

Question 7.
In an electromagnetic wave in free space the rms value of the electric field is 3 V m . The peak value of the magnetic field is………………………..
(a) 1.414 x 10^-8 T
(b) 1.0 x 10^-8 T
(c) 2.828 x 10^-8 T
(d) 2.0 x 10^-8 T
Answer:
(a) 1.414 x 10^-8 T

Question 8.
Two point white dots are 1 mm apart on a black paper. They are viewed by eye of pupil diameter 3 mm approximately. The maximum distance at which these dots can be resolved by the eye is, [take wavelength of light, λ = 500 nm]
(a) 1m
(b) 5m
(c) 3m
(d) 6m
Answer:
(b) 5m
Hint:
Resolution limit sin θ =

Question 9.
Two mirrors are kept at 60° to each other and a body is placed at middle. The total number of images formed is ……………..
(a) six
(b) four
(c) five
(d) three
Answer:
(a) six
Hint:
Number of images formed \(n=\frac{360}{\theta}-1=\frac{360}{60}-1=5\)

Question 10.
The threshold wavelength for a metal surface whose photoelectric work function is 3.313 eV is
{a) 4125 Å
(b) 3750  Å
(c) 6000 Å
(d) 2062.5 Å
Answer:
(b) 3750  Å

Question 11.
Suppose an alpha particle accelerated by a potential of V volt is allowed to collide with a nucleus whose atomic number is Z, then the distance of closest approach of alpha particle to the nucleus is…..

Answer:
(c)

Question 12.
The speed of the particle, that can take discrete values is proportional to ……………
(a) n^-3/2
(b) n^-3
(c) n^1/2
(d) n
Answer:
(d) n
Hint:
\(P=m v=\frac{n h}{2 a} ; V \propto n\)

Question 13.
Doping semiconductor results in ………………………………
(a) The decrease in mobile charge carriers
(b) The change in chemical properties
(c) The change in the crystal structure
(d) The breaking of the covalent bond
Answer:
(c) The change in the crystal structure

Question 14.
The signal is affected by noise in a communication system …………………….
(a) At the transmitter
(b) At the modulator
(c) In the channel
(d) At the receiver
Answer:
(c) In the channel

Question 15.
The technology used for stopping the brain from processing pain is…………………………..
(a) Precision medicine
(b) Wireless brain sensor
(c) Virtual reality
(d) Radiology
Answer:
(c) Virtual reality

Part – II

Answer any six questions. Question No. 21 is compulsory. [6 x 2 = 12]

Question 16.
Define ‘Electric field’.
Answer:
The electric field at the point P at a distance r from the point charge q is the force experienced by a unit charge and is given by
\(\overrightarrow{\mathrm{E}}=\frac{\overrightarrow{\mathrm{F}}}{q_{0}}\)
The electric field is a vector quantity and its Sl unit is Newton per Coulomb (NC^-1).

Question 17.
State the principle of potentiometer.
Answer:
The basic principle of a potentiometer is that when a constant current flows through a wire of uniform cross-sectional area and composition, the potential drop across any length of the wire is directly proportional to that length.

Question 18.
Compute the intensity of magnetisation of the bar magnet whose mass, magnetic moment and density are 200 g, 2 A m² and 8 g cm^-3, respectively.
Answer:

Question 19.
What is displacement current?
Answer:
The displacement current can be defined as the current which comes into play in the region in ‘ which the electric field and the electric flux are changing with time.

Question 20.
What is principle of reversibility?
Answer:
The principle of reversibility states that light will follow exactly the same path if its direction of travel is reversed.

Question 21.
Calculate the de Broglie wavelength of a proton whose kinetic energy is equal to. 81.9 x 10¹⁵ (Given: mass of proton is 1836 times that of electron).
Answer:

Question 22.
Give the symbolic representation of alpha decay, beta decay and gamma decay.
Answer:
Alpha decay: The alpha decay process symbolically in the following way
Beta decay: β decay is represented by \(_{ z }^{ A }X\rightarrow _{ z,-1 }^{ A }Y+e^{ + }+v\)
Gamma decay: The gamma decay is given \(\mathrm{z} \mathrm{X}^{*} \rightarrow_{Z}^{\mathrm{A}} \mathrm{X} \)+ gamma(y)rays

Question 23.
Explain the need for a feedback circuit in a transistor oscillator.
Answer:
The circuit used to feedback a portion of the output to the input is called the feedback network. If the portion of the output fed to the input is in phase with the input, then the magnitude of the input signal increases. It is necessary for sustained oscillations.

Question 24.
Give the factors that are responsible for transmission impairments.
Answer:

• Attenuation
• Distortion (Harmonic)
• Noise

Part – III

Answer any six questions. Question No. 32 is compulsory. [6 x 3 = 18]

Question 25.
A water molecule has an electric dipole moment of 6.3 x 10 Cm. A sample contains 10 water molecules, with all the dipole moments aligned parallel to the external electric field of magnitude 3 x 10^s NC^-1. How much work is required to rotate all the water molecules from θ = 0° to 90°?
Answer:
When the water molecules are aligned in the direction of the electric field, it has minimum potential energy. The work done to rotate the dipole from θ = 0° to 90° is equal to the potential energy difference between these two configurations.
W = ΔU = U(90°) – U(0°)
As we know, U = -pE cos θ, Next we calculate the work done to rotate one water molecule
from θ = 0° to 90°,
For one water molecule, W = – pE cos 90° + pE cos 0° = pE
W = 6.3 x10^-30 x 3 x 10⁵ = 18.9 x 10^-25
For 10²² water molecules, the total work done is W_tot = 18.9x 10 ²⁵ x 10²² = 18.9 x 10 ³ J

Question 26.
What are the properties of an equipotential surface?
Answer:
Properties of equipotential surfaces
(i) The work done to move a charge q between any two points A and B,
W = q (V_B – V_A ). If the points A and B lie on the same equipotential surface, work done is zero because V_B – V_A

(ii) The electric field is normal to an equipotential surface. If it is not normal, then there is a component of the field parallel to the surface. Then work must be done to move a charge between two points on the same surface. This is a contradiction. Therefore the electric field must always be normal to an equipotential surface.

Question 27.
An electronics hobbyist is building a radio which requires 150 ft in her circuit, but she has only 220 Ω 79 Ω and 92 Ω resistors available. How can she connect the available resistors to get desired value of resistance?
Answer:
Required effective resistance = 150 ft
Given resistors of resistance, R = 220 ft, R = 79 ft, R = 92 ft
Parallel combination of R₁ and R₂

Question 28.
What is magnetic permeability?
Answer:
Magnetic permeability: The magnetic permeability can be defined as the measure of ability of the material to allow the passage of magnetic field lines through it or measure of the capacity of the substance to take magnetisation or the degree of penetration of magnetic field through the substance.

Question 29.
A circular metal of area 0.03 m² rotates in a uniform magnetic field of 0.4 T. The axis of rotation passes through the centre and perpendicular to its plane and is also parallel to the field. If the disc completes 20 revolutions in one second and the resistance of the disc is 4 Ω calculate the induced emf between the axis and the rim and induced current flowing in the disc.
Answer:
A = 0.03 m²; B = 0.4T; f = 20rps; R = 4Ω
Area covered in 1 sec = Area of the disc x frequency
= 0.03 x 20 = 0.6 m²

Question 30.
Give the characteristics of image formed by a plane mirror.
Answer:

• The image formed by a plane mirror is virtual, erect, and laterally inverted.
• The size of the image is equal to the size of the object.
• The image distance far behind the mirror is equal to the object distance in front of it.
• If an object is placed between two plane mirrors inclined at an angle 0, then the number of images n formed is as,\(n=\left(\frac{360}{\theta}-1\right)\)

Question 31.
An electron and an alpha particle have same kinetic energy. How are the de Broglie wavelengths associated with them related?
Answer:

Question 32.
Assuming V_CEsat = 0.2 V and β = 50, find the minimum base current (I_B) required to drive the transistor given in the figure to saturation.
Answer:

V_CEsat = 0.2 V and β = 50
V_CE = V_CC -I_C R_C
0.2= 3 – I_c(1 k)

Question 33.
Mention any two advantages and disadvantages of Robotics.
Answer:
(i) Advantages of Robotics:

• The robots are much cheaper than humans.
• Robots never get tired like humans. It can work for 24 x 7. Hence absenteeism in work place can be reduced.
• Robots are more precise and error free in performing the task.

(ii) Disadvantages of Robotics:

• Robots have no sense of emotions or conscience.
• They lack empathy and hence create an emotionless workplace.
• If ultimately robots would do all the work, and the humans will just sit and monitor them* health hazards will increase rapidly.

Part – IV

Answer all the questions. [5 x 5 = 25]

Question 34.
(a) Derive an expression for electrostatic potential energy of the dipole in a uniform electric field.
Answer:
Expression for electrostatic potential energy of the dipole in a uniform electric field:
Considera dipole placed in the uniform electric field \(\overrightarrow{\mathrm{E}}\) placed in the uniform electric field \(\overrightarrow{\mathrm{E}}\) . A dipole experiences a torque when kept in an uniform electric field E.

This torque rotates the dipole to align it with the direction of the electric field. To rotate the dipole (at constant angular velocity) from its initial angle θ’ to another angle θ against the torque exerted by the electric field, an equal and opposite external torque must be applied on the dipole. The work done by the external torque to rotate the dipole from angle θ’ to θ at constant angular velocity is

This work done is equal to the potential energy difference between the angular positions 0 and 0′. U(θ) – (Uθ’) = ΔU = -pE cos θ + pE cos θ’.

If the initial angle is = θ’ = 90° and is taken as reference point, then U(θ’) + pE cos 90° = 0. The potential energy stored in the system of dipole kept in the uniform electric field is given by.
U = -pE cos θ = -p-E  ……………. (3)

In addition to p and E, the potential energy also depends on the orientation θ of the electric dipole with respect to the external electric field.

The potential energy is maximum when the dipole is aligned anti-parallel (θ = Jt) to the external electric field and minimum when the dipole is aligned parallel (θ = 0) to the external electric field.

[OR]

(b) Deduce the relation for the magnetic induction at a point due to an infinitely long straight conductor carrying current.
Answer:
Magnetic field due to long straight conductor carrying current: Consider a long straight wire NM with current I flowing from N to M. Let P be the point at a distance a from point O.
Consider an element of length dl of the wire at a distance l from point O and \(\vec{r} \) be the vector joining the element dl with the point P. Let θ be the angle between \(d \vec{l} \text { and } \vec{r}\). Then, the magnetic field at P due to the element is
\(d \overrightarrow{\mathrm{B}}=\frac{\mu_{0} \mathrm{Id} l}{4 \pi r^{2}} \sin \theta\)(unit vector perpendicular to \(d \vec{l} \text { and } \vec{r}\)

The direction of the field is perpendicular to the plane of the paper and going into it. This can be determined by taking the cross product between two vectors \(d \vec{l} \text { and } \vec{r}\)
(let it be \(\hat{n}\)). The net magnetic field can be determined by integrating equation with proper limits. \(\overrightarrow{\mathrm{B}}=\int d \overrightarrow{\mathrm{B}}\) From the figure, in a right angle triangle PAO,

This is the magnetic field at a point P due to the current in small elemental length. Note that we have expressed the magnetic field OP in terms of angular coordinate i.e. θ. Therefore, the net magnetic field at the point P which can be obtained by integrating \(d \overrightarrow{\mathrm{B}} \) by varying the angle from θ = φ₁ to θ =φ₂ is

For a an infinitely long straight wire, 1 =0 and 2 =, the magnetic field is \(\overrightarrow{\mathrm{B}}=\frac{\mu_{0} I}{2 \pi a} \hat{n} \) ………… (3)
Note that here \(\hat{n} \) represents the unit vector from the point O to P.

Question 35.
(a) Obtain an expression for motional emf from Lorentz force.
Answer:
Motional emf from Lorentz force: Consider a straight conducting rod AB of length l in a uniform magnetic field \(\vec{B}\) which is directed perpendicularly into the plane of the paper. The length of the rod is normal to the magnetic field. Let the rod move with a constant velocity \(\vec{v}\) towards right side. When the rod moves, the free electrons present in it also move with same velocity \(\vec{v}\) in B. As a result, the Lorentz force acts on free electrons in the direction from B to A and is given by the relation  \(\overrightarrow{\mathrm{F}}_{\mathrm{B}}\)=-
\( e(\vec{v} \times \overrightarrow{\mathrm{B}}) \) …………. (1)

The action of this Lorentz force is to accumulate the free electrons at the end A. This accumulation of free electrons produces a potential difference across the rod which in turn establishes an electric field E directed along BA. Due to the electric field \(\overrightarrow{\mathrm{E}}\), the coulomb force starts acting on the free electrons along AB and is given by
\(\overrightarrow{\mathrm{F}}_{\mathrm{E}}=-e \overrightarrow{\mathrm{E}}\) ……….. (2)

The magnitude of the electric field E keeps on increasing as long as accumulation of electrons at the end A continues. The force \(\overrightarrow{\mathrm{F}}_{\mathrm{B}}\) also increases until equilibrium is reached. At equilibrium, the magnetic Lorentz force \(\overrightarrow{\mathrm{F}}_{\mathrm{B}}\) and the coulomb force F balance each other and no further accumulation of free electrons at the end A takes place,
i.e

The potential difference between two ends of the rod is
V= El
V= vBl
Thus the Lorentz force on the free electrons is responsible to maintain this potential difference and hence produces an emf

ε = B lv    ………….. (4)
As this emf is produced due to the movement of the rod, it is often called as motional emf.

[OR]

(b) Explain the Maxwell’s modification of Ampere’s circuital law.
Answer:
Maxwell argued that a changing electric field between the capacitor plates must induce a magnetic field. As currents are the usual sources of magnetic fields, a changing electric field must be associated with a current. Maxwell called this current as the displacement current.

If ‘A’ be the area of the capacitor plates and ‘cf be the charge on the plates at any instant ‘f during the charging process, then the electric field in the gap will be

But \(\frac{d q}{d t}\) is the rate of change of charge on the capacitor plates. It is called displacement current and given by \(\mathrm{I}_{d}=\frac{d q}{d t}=\varepsilon_{0} \frac{d \Phi_{\mathrm{E}}}{d t}\)

This is the missing term in Ampere’s Circuital Law. The total current must be the sum of the
conduction current I_c Hence, the modified form of the ampere’s law.
\(\oint_{c} \overrightarrow{\mathrm{B}} \cdot \overrightarrow{d l}=\mu_{0}\left(\mathrm{I}_{c}+\varepsilon_{0} \frac{d \Phi_{\mathrm{E}}}{d t}\right)\)

Question 36.
(a) Obtain the equation for resolving power of microscope.
Answer:
Resolving power of microscope: The diagram related to the calculation of resolution of microscope. A microscope is used to see the details of the object under observation. The ability of microscope depends not only in magnifying the object objective but also in resolving two points on the object separated by a small distance d_min  Smaller the value of d_min better will be the resolving power of the microscope.

The radius of central maxima is, \(r_{0}=\frac{1.22 \lambda v}{a}\) . In the place of focal length f we have the image distance v. If the difference between the two points on the object to be resolved is d_min, then the magnification m is, \(m=\frac{r_{o}}{d_{\min }}\)


To further reduce the value of d_min the optical path of the light is increased by immersing the objective of the microscope into a bath containing oil of refractive index n.

Such an objective is called oil immersed objective. The term n sin β is called numerical aperture NA.

[OR]

(b) Derive an expression for de Broglie wavelength of electrons.
Answer:
An electron of mass m is accelerated through a potential difference of V volt. The kinetic energy acquired by the electron is given by
\(\frac{1}{2} m v^{2}=e \mathrm{V}\)
Therefore, the speed v of the electron is \(v=\sqrt{\frac{2 e \mathrm{V}}{m}}\)
Hence, the de Broglie wavelength of the electron is \(\lambda=\frac{h}{m v}=\frac{h}{\sqrt{2 e m \mathrm{V}}}\)
Substituting the known values in the above equation, we get

For example, if an electron is accelerated through a potential difference of 100V, then its de Broglie wavelength is 1.227 Å. Since the kinetic energy of the electron, K = eV, then the de Broglie wavelength associated with electron can be also written as
\(\lambda=\frac{h}{\sqrt{2 m \mathrm{K}}}\)

Question 37.
(a) Explain the variation of average binding energy with the mass number by graph and discuss its features.
Answer:
We can find the average binding energy per nucleon \(\overline{\mathrm{BE}}\).
It is given by

The average binding energy per nucleon is the energy required to separate single nucleon from the particular nucleus. \(\overline{\mathrm{BE}}\) is plotted against A of all known nuclei.

Important inferences from of the average binding energy curve:

• The value of BE rises as the mass number increases until it reaches a maximum value of 8.8 MeV for A= 56 (iron) and then it slowly decreases.
• The average binding energy per nucleon is about 8.5 MeV for nuclei having mass number between A = 40 and 120. These elements are comparatively more stable and not radioactive.
• For higher mass numbers, the curve reduces slowly and BE for uranium is about 7.6 MeV. They are unstable and radioactive.  If two light nuclei with A < 28 combine with a nucleus with A < 56, the binding energy per nucleon is more for final nucleus than the initial nuclei. Thus, if the lighter elements combine to produce a nucleus of medium value A, a large amount of energy will be released. This is the basis of nuclear fusion and is the principle of the hydrogen bomb.
• If a nucleus of heavy element is split (fission) into two or more nuclei of medium value A, the energy released would again be large. The atom bomb is based on this principle and huge energy of atom bombs comes from this fission when it is uncontrolled.

[OR]

(b) State Boolean laws. Elucidate how they are used to simplify Boolean expressions with suitable example.
Answer:
Laws of Boolean Algebra: The NOT, OR and AND operations are \(\bar{A}\), A + B, A.B are the Boolean operations. The results of these operations can be summarised as:

Complement law:

The complement law can be realised as \(\overline{\mathrm{A}}\) = A

Commutative laws
A + B = B +A
A . B = B . A

Associative laws
A + (B + C) = (A + B) + C
A . (B . C) = (A .B) . C

Distributive laws
A( B + C) = AB + AC
A + BC = (A + B) (A + C)
The above laws are used to simplify complicated expressions and to simplify the logic circuitry.

Question 38.
(a) Modulation helps to reduce the antenna size in wireless communication – Explain. Antenna size:
Answer:
Antenna is used at both transmitter and receiver end. Antenna height is an important parameter to be discussed. The height of the antenna must be a multiple of \(\frac{\lambda}{4}\)
\(h=\frac{\lambda}{4}\) ……………….. (1)
where X is wavelength \(\left(\lambda=\frac{c}{v}\right), c\) c is the velocity of light and v is the frequency of the signal v to be transmitted.

An example
Let us consider two baseband signals. One signal is modulated and the other is not modulated. The frequency of the original baseband signal is taken as v = 10 kHz while the modulated signal is v = 1 MHz. The height of the antenna required to transmit the original baseband signal of frequency
v = 10kHz is

The height of the antenna required to transmit the modulated signal of frequency v = 1 MHz is

Comparing equations (2) and (3), we can infer that it is practically feasible to construct an antenna of height 75 m while the one with 7.5 km is not possible. It clearly manifests that modulated signals reduce the antenna height and are required for long distance transmission.

[OR]

(b) What are the possible harmful effects of usage of Nanoparticles? Why?
Answer:
Possible harmful effects of usage of Nanoparticles:

The research on the harmful impact of application of nanotechnology is also equally important and fast developing. The major concern here is that the nanoparticles have the dimensions same as that of the biological molecules such as proteins. They may easily get absorbed onto the surface of living organisms and they might enter the tissues and fluids of the body.

The adsorbing nature depends on the surface of the nanoparticle. Indeed, it is possible to deliver a drug directly to a specific cell in the body by designing the surface of a nanoparticle so that it adsorbs specifically onto the surface of the target cell.

The interaction with living systems is also affected by the dimensions of the nanoparticles. For instance, nanoparticles of a few nanometers size may reach well inside biomolecules, which is not possible for larger nanoparticles. Nanoparticles can also cross cell membranes.

It is also possible for the inhaled nanoparticles to reach the blood, to reach other sites such as the liver, heart or blood cells. Researchers are trying to understand the response of living organisms to the presence of nanoparticles of varying size, shape, chemical composition and surface characteristics.

Students can Download Tamil Nadu 12th English Model Question Paper 3 Pdf, Tamil Nadu 12th English Model Question Papers helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

TN State Board 12th English Model Question Paper 3

Time: 2 1/2 Hours
Maximum Marks: 90

General Instructions:

• The question paper comprises of four parts.
• You are to attempt all the sections in each part. An internal choice of questions is provided wherever applicable.
• All questions of Part I, II, III, and IV are to be attempted separately.
• Question numbers 1 to 20 in Part I are Multiple Choice Questions of one mark each. These are to be answered by writing the correct answer along with the corresponding option code.
• Part II has got two sections. The questions are of two marks each. Question numbers 21 to 26 in Section I and Question numbers 27 to 30 in Section II are to be answered in about one or two sentences each.
• Question numbers 31 to 40 in Part III are of three marks each and have been divided in three sections. These are to be answered as directed.
• Question numbers 41 and 47 in Part IV are of five marks each. These are to be answered as directed.

Part -1

I. Answer all the questions. [20 x 1= 20]
Choose the correct synonyms for the underlined words from the options given:

Question 1.
One is liable to put in too much milk.
(a) certain (b) responsible (c) eager (d) likely
Answer:
(b) responsible

Question 2.
Two children had given me a profound lesson.
(a) shallow (b) intense (c) modest (d) humble
Answer:
(b) intense

Question 3.
I cooked them over the fierce flames.
(a) benign (b) mild (c) ferocious (d) sublime
Answer:
(c) ferocious

Choose the correct antonyms for the underlined words from the options given:

Question 4.
I have liberty to be indifferent to you.
(a) disinterested (b) heedless (c) unconcerned
Answer:
(c) unconcerned

Question 5.
Liberties of all may be preserved.
(a) damaged (b) retained (c) conserved
Answer:
(a) damaged

Question 6.
This trolley was commandeered by an intrepid crew of two.
(a) adventurous (b) daring (c) bold (d) timid
Answer:

Question 7.
Choose the correct combination for the compound word ‘mind blowing’.
(a) Noun + Verb (b) Noun + Gerund (c) Gerund + Noun (d) Preposition + Noun
Answer:
(b) Noun + Gerund

Question 8.
Choose the correct expansion of IIM.
(a) Indian Institute of Minorities (b) Indian Institute of Managers (c) Indian Institute of Marine (d) Indian Institute of Management
Answer:
(d) Indian Institute of Management

Question 9.
Choose the meaning of the foreign word in the sentence:
Bhaskar was John’s Protege.
(a) villain (b) relative (c) disciple (d) superior
Answer:
(d) superior

Question 10.
Choose the right combination for the blended word Webinar.
(a) Web + Minar (b) Website + Seminar (c) Web + Portal (d) Web + Seminar
Answer:
(b) Website + Seminar

Question 11.
Choose the clipped word for ‘veterinarian’.
(a) vegan (b) vegin (c) vet (d) veteran
Answer:
(c) vet

Question 12.
Someone who makes animated films with a series of drawings on paper or on the computer is called ………………….. .
(a) infanticide (b) animator (c) parricide (d) fratricide
Answer:
(b) animator

Question 13.
Form a derivative by adding the right suffix to the word ‘hostile’.
(a) -eous (b) -ly (c) -y (d) -ity
Answer:

Question 14.
Fill in the blanks with a suitable relative pronoun. I remember a time radio shows were popular.
(a) when (b) where (c) which (d) whose
Answer:
(d) whose

Question 15.
Fill in the blanks with a suitable preposition. My friend has been living in UK ………………………… two years.
(a) since (b) in (c) for (d) at
Answer:
(a) since

Question 16.
Choose the correct question tag for the following statement. I shouldn’t have lost my temper, …………………………?
(a) shall I (b) should I (c) wouldn’t I (d) won’t I
Answer:
(c) wouldn’t I

Question 17.
Choose the suitable meaning or idiom found in the following sentence.
His arrogant behavior with others has left him ‘high and dry’.
(a) to be penniless (b) to be very sick (c) to be very famous (d) isolated
Answer:
(d) isolated

Question 18.
Substitute the underlined word with the appropriate polite alternative.
Joseph was half bald at 25.
(a) follicular challenged (b) hairless (c) hairy (d) glaring
Answer:
(a) follicular challenged

Question 19.
Choose the correct sentence pattern for the following sentence. What is important is what you have left.
(a) SVC (b) SVOCA (c) SVOAA (d) SVCA
Answer:
(a) SVC

Question 20.
Fill in the blank with a suitable phrasal verb.
When I …………………….. my own recipe, I find eleven outstanding points.
(a) get into (b) look out (c) put into (d) look through
Answer:
(d) look through

Part II
Section – 1

Read the following sets of poetic lines and answer any four from it. [4 x 2 = 8]

Question 21.
“What could they offer us for bait?
Our captain was brave and we were true…”
(a) What do you mean by bait?
(b) Why did the soldiers believe that they were invincible?
Answer:
(а) Bait means something intended to entice someone to do something usually dishonorable.
(b) The soldiers believed that they were invincible because their captain was brave and they were loyal.

Question 22.
“For your sakes, shall the tree be ever dear.
Blent with your images, it shall arise
In memory, till the hot tears blind mine eyes!”
(a) For whose sake will the trees be dear to the poet?
(b) Whose images bring out hot tears?
Answer:
(a) For the sake of three younger Dutts who died of Tuberculosis, the tree will be dear to Torn Dutt.
(b) The images of siblings who died due to TB bring out hot tears.

Question 23.
“All the world’s a stage
And all the men and women merely players:
They have their exits and their entrances;
And one man in his time plays many parts,
His acts being seven ages.”
(a) How are the men and women of this world?
(b) Explain: ‘They have their exits and their entrances’.
Answer:
(a) The men and women of this world are just like players on the stage of life.
(b) They take birth and enter the world. They die and depart from the world.

Question 24.
“And this might stand him for the storms and serve him for humdrum monotony”
(a) What does the poet mean by storms?
(b) What can help the son overcome “the boring routine” in life?
Answer:
(a) The poet means life’s challenges by ‘storms’.
(b) One can overcome ‘the boring routine’ by keeping a strong steel/rock-like will power and face life boldly.

Question 25.
“…., for my purpose holds
To sail beyond the sunset, and the baths Of all the western stars, until I die”
(a) What was Ulysses’ purpose in life?
(b) How long would his venture last?
Answer:
(a) Ulysses proposes to sail beyond sunset and baths. His goal is not death but is in death. He seeks life in death. Ordinary mortals can’t reach ‘Happy isles’ or baths while they are alive. Ulysses wants to find direct evidence of spiritual reality after death. He wants to venture into the unknown.
(b) His venture would last until he confronts his death.

Question 26.
“Full-galloping: nor bridle drew
Until he reached the mound.”
(a) Why was the rider in a hurry?
(b) Where did the soldier stop? Why?
Answer:
(a) The rider was carrying an urgent message to Napoleon Bonaparte.
(b) The soldier stopped at the mound. Napoleon Bonaparte was expecting news about the outcome of the battle at Ratisbon.

Section – 2

Answer any three of the following questions. [3 x 2 = 6]

Question 27.
Report the following dialogue:
Answer:
Silas : Dad, John is visiting us today.
Dad : Did you tell your mother about it?
Silas told his dad that John was visiting them that day. Dad asked Silas if he had told his mother about it.

Question 28.
He must carry out my orders. Otherwise he will be sacked, (combine using if)
Answer:
If he does not carry out my orders, he will be sacked.

Question 29.
Rewrite the sentence making an inversion in the conditional clause.
If it had not rained yesterday, we would have finished painting the walls.
Answer:
Had it not rained yesterday, we would have finished painting the walls.

Question 30.
He said that he was so disappointed that he would not try again. (Change the following into a simple sentence)
Answer:
He said that he was too disappointed to try it again.

Part-III
Section -1

Explain any two of the following with reference to the context. [2 x 3 = 6]

Question 31.
A creeper climbs, in whose embraces bound No other tree could live.
Answer:
Reference: These words are from the poem, ‘Our Casuarina Tree” written by Torn Dutt.

Context: The poet says this while appreciating the strength of her Casuarina tree.

Explanation: The creeper saps the tree for its survival and growth. But the tree treats the creeper’s tight hold as a lover’s embrace. It ignores bite marks oflove.lt allows the creeper to lean on its trunk and live. The tree also grows stout and strong.

Question 32.
Is second childishness and mere oblivion
Answer:
Reference: These lines are from the poem, ‘All the world’s a stage’ written by William Shakespeare.

Context: The poet says this while man gets ready to leave this world (i.e.) the last stage of his life on this lonely planet.

Explanation: In this stage, man becomes totally forgetful. He loses his teeth, eyesight and taste. He loses all his senses of perception. Like a baby, he can’t do anything on his own. So, the poet calls this stage “second childhood” when the old man behaves in a childish manner.

Question 33.
Tell him too much money has killed men and left them dead years before burial:
Answer:
Reference: These lines are from the poem, ‘A Father to his Son” written by Carl August Sandburg.

Context: The poet says these words while dwelling on the evil effects of amassing wealth beyond basic needs.

Explanation: Oliver Goldsmith says, “Where wealth accumulates, man decays.” The poet says that a man who amasses wealth against ethical principles is spiritually dead. The wealth earned should benefit a large number of people and not the individual who initiated the wealth.

Section – 2

Answer any two of the following questions in about 30 words. [2 x 3 = 6]

Question 34.
What are the author’s views on China tea?
Answer:
China tea has virtues which are not to be despised. It is economic. One can drink it without milk. But there is not much stimulation in it. One does not feel wiser, braver or more optimistic after drinking it.

Question 35.
Why does Dr. Barnard describe the blind boy as a ‘walking horror’?
Answer:
At the time of the grand prix, the boy was a walking horror. His face was disfigured. A long flap of skin was hanging from the side of his neck to his body. As the wound healed around his neck, his lower jaw became gripped in a mass of fibrous tissue. The only way he could open his mouth was to raise his head.

Question 36.
How would ‘liberty’ cause universal chaos?
Answer:
When liberty is used without accommodating the interests of others, it results in universal chaos. Everybody would be getting in everybody else’s way. Nobody would get anywhere. Individual liberty would become a social anarchy.

Section – 3

Answer any three of the following questions in about 30 words. [3 x 3 = 9]

Question 37.
Study the pie chart given and answer the questions that follow.

Expenditure of the State Government Public Welfare
(a) Which is the sector for which the State Government spends the most?
(b) What is the percent of expenditure made by the State Government on Public Welfare?
(c) What is the percent of expenditure made by the State Government on Transport?
Answer:
(a) The State Government spends for Education the most.
(b) Eighteen percent of the expenditure by the state government is on public welfare.
(c) Thirty percent of the expenditure by the state government is on transport.

Question 38.
Write a dialogue of minimum 3 exchanges between a reporter and an entrepreneur.
Answer:
Reporter: How did you become the owner of such a large chain of grocery stores?
Brown : I couldn’t read nor write and being an uneducated person I lost my job.
Reporter: What do you mean by saying that the reason is because you could not read or write?
Brown : Yes because of that, I had to leave my job as the vicar of St. Peter’s church.
Reporter: Why did you leave your job as vic’ar of St. Peter’s church?
Brown : I was sent away by the Priest as I couldn’t read nor write as the Vicar.

Question 39.
Describe the process of recycling waste materials.
Answer:
The first step is to collect the materials that can be recycled such as Aluminum cans, Car Bumpers, Newspapers and paper towels, Motor oil, Nails, Trash bags, Egg cartons and Laundry detergent bottles.

Once the items have been collected the next step is to find a secondary use of the material. Recycled material is used in many manufacturing processes and many companies have found very innovative uses for the materials.

The next step in the process is to purchase goods made from recycled materials. When in the grocery store check out the labelling and often you will see where the product is made with a percentage of post-consumer products.

Question 40.
Complete the proverbs using the word given below.
(a) One man’s meat is another man’s ………………… (prison, poison, gift)
(b) People who live in glass houses should not throw ………………… (water, fruits, stones)
(c) Every cloud has a silver ………………… (lining, finish, colour)
Answer:
(a) poison (b) stones (c) lining

Part – IV

Answer the following questions: [7 x 5 = 35]
Answer in a paragraph in about 150 words.

Question 41.
Describe the ‘Grand Prix’ at Cape Town’s Red Cross Children’s Hospital.
Answer:
The author describes the event as “the Grand Prix of Cape Town’s Red Cross Childrens’ Hospital”. A nurse had left a breakfast trolley unattended. Very soon this trolley was commandeered by a daring crew of two, a driver and a mechanic. The mechanic provided motor power by galloping along behind the trolley head down. While the driver, seated on the lower deck held on with one hand and steered it by scrapping his foot on the floor. The choice of roles was easy because the mechanic was totally blind and the driver had only one arm. It was better than Indianapolis 500 car race. Patients shouted and cheered the boys. There was a grand finale of scattered plates and silverware before the nurse and ward sister took control of the situation.

[OR]

How did Hillary and Tenzing prepare themselves before they set off to the summit?
Answer:
They started up their cookers and drank lots of lemon juice and sugar. Then they took sardines and biscuits. Hillary cleaned the ice off the oxygen sets. He rechecked and tested them. He had removed his boots which had become wet the day before. They were now frozen solid. It would be very challenging to start climbing ice-cold Himalayas with such wet and chilling boots. So, he cooked them over the fierce flame of Primus and managed to soften them up.

They were also conscious of the probabilityof braving snow storms during the ascent. They fortified their clothing with wind proof and also pulled three pairs of gloves silk, woollen, and windproof on to their hands. At 6.30 am they crawled out of their tent into the snow. They hoisted their 30 lb. of oxygen gear on their backs. Connecting their oxygen masks they turned on the valves to bring life-giving oxygen into their lungs. Taking a few deep breaths, they got ready to go.

Question 42.
How does nature communicate with the Toru Dutt?
Answer:
Like Wordsworth, Toru Dutt is also a great lover of nature. She has also had mystical experiences in communion with nature. The emotional bonding between herself and the giant Casuarina tree is beyond reason. When she is away on the shores of Italy and France, she could distinctly hear the dirge-like murmer of her beloved tree who obviously missed her. She could perceive it as the tree’s lament and eerie speech expressing its anguish over the long spells of her absence.

Ordinary human eyes will fail to perceive the distinct communication of the Casuarina tree. But through the eyes of faith, similar to William Wordsworth’s inward eye in the poem ‘Daffodils’ it is possible. She was able to vividly see in her inner vision the sublime form of the Casuarina tree. The surprising thing is that she was able to see the tree in its prime in her own “loved native clime.”

[OR]

What is Ulysses’ clarion call to his sailors? How does he inspire them?
Answer:
In the third part of the poem, Ulysses makes a clarion call to his hearty compatriots (i.e.) mariners. They have been with him both during ‘thick and thin’ or thunders or sunshine. They had frolicsome time fighting along with Ulysses against great warriors and Gods in the past. Ulysses does not want to live in memory of glory. He believes they need not waste away their precious time in nostalgic memories just recounting their escapades to younger generation. He is conscious of the impending death in old age. But he tells it is not “too late to seek a newer world”.

The many “voices of the ocean” call out to the mariners to resume voyage. He does not want his compatriots to miss even an hour which could provide them novel experiences in their voyage. He persuades his compatriots to gather at the port as the sails are already puffing up welcoming them all. Their life would be one of fulfillment only when they venture out into the unknown on the seas. He uses an emotional bait to his mariners.

He highlights the probable outcome of their voyage. They might reach the “Happy Isles” (i.e.) great paradise and meet Achilles, their war hero. No matter how much strength they have, they still have some “strength of will” left to strive, to seek, to find, and not to yield.

Question 43.
Write a paragraph of about 150 words by developing the following hints:
Children reaction – touch of sunlight – tan themselves – teacher warns – take off jackets – jungle in the Venus – colour of stones – ran among trees – hide and seek – breathed off the fresh air – blessed sea of soundlessness – savoured everything – mirth for one hour.
Answer:
Children get really excited. They want to see the touch of sunlight on all form of life in the planet. They want to tan themselves in the new found warmth of the Sun. Children persist that they be allowed to go out to the Sun. The teacher allows them with a warning that they must be back in two hours. They start running and turning their faces up to the sky and feeling the Sun on their cheeks like a warm iron. They take off their jackets to allow the Sun to bum their arms.

They gladly shouted “Oh, its better than Sun lamps. Children stood in the great jungle in the Venus. The jungle was in the colour of stones as they had not seen the Sun for years. The children lay out laughing on the jungle mattresses and heard it sigh and squeak under them resilient and alive. They ran among the trees, they slipped and fell and pushed one another.

They played hide and seek. But most of them squinted at the sun until tears ran down their faces. They put their hands up to the yellowness and the amazing blueness, they breathed off the fresh air and listened to the silence in a blessed sea of soundlessness. They looked at everything and savoured everything. Like animals escaped from their caves, they ran shouting in circles. Their mirth continued for one hour.

[OR]

Lord Weston – judge – pompous and vain – secretary Roger – displeasure over Roger’s request – piece of paper – warning – legal punishments – 15th of March – fair judgement – unperturbed by threat – precautionary measures – assassination attempt – a gardener – Weston’s absent-mindedness.
Answer:
‘Remember Caesar’ is a light hearted comedy. The name Caesar is the name of a tragic hero Julius Caesar in one of the plays of William Shakespeare. Weston gives an appointment to Mr. Caesar to discuss rose tree planting work in his garden. Just to remind him of the proffered appointment, he scribbles two words “Remember Caesar” and keeps that scrap
of paper in his coat pocket and has forgotten about it. On seeing that note, Lord Weston is shocked. Roger, the assistant of the judge elevates him to the level of a tragic hero.

He flatters the judge that his death could be a great loss to England as he was a great impartial judge. Mrs. Weston’s entry lightens up the whole drama and the tragedy transitions into a dark comedy. Lady Weston keeps hinting about earlier attempts when he was eating a game pie. When Weston says he has instructed Roger to barricade all doors, her immediate worry is about the grocery awaited. She asks if he was expecting both French and Dutch together in the attempt to assassinate. Lady Weston doesn’t want to send away the cook. She is practical.

She wants her to stay back to cook his pet dishes. Lady Weston brings a handful of candles to keep the room lit if Mr. Weston has to stay underground for a while. A velvet coat is construed as an infernal machine that could blow up the whole place is smothered with books inside a pail of water. The arrival of Mr. Caesar only sorts out the knot. The judge remembers to meet Mr. Caesar on 15th March.

Question 44.
Write a summary or Make notes of the following passage.
Answer:
When we survey our lives and efforts we soon observe that almost the whole of our actions and desires are bound up with the existence of other human beings. We notice that whole nature resembles that of the social animals. We eat food that others have produced, wear clothes that others have made, live in houses that others have built. The greater part of our knowledge and beliefs has been passed on to us by other people though the medium of a language which others have created. Without language and mental capacities, we would have been poor indeed comparable to higher animals.

We have, therefore, to admit that we owe our principal knowledge over the least to the fact of living in human society. The individual if left alone from birth would remain primitive and beast like in his thoughts and feelings to a degree that we can hardly imagine. The individual is what he is and has the significance that he has, not much in virtue of the individuality, but rather as a member of a great human community, which directs his material and spiritual existence from the cradle to grave.

Summary

No. of words given in the original passage: 192
No. of words to be written in the summary: 192/3 = 64 ± 5

Rough Draft

Being social animals, human beings have their actions and desires bound up with society. In matter of food clothes knowledge and belief they are interdependent with one another. We eat food that others have procedure Wear clothes that others have made, live in houses that others have built. They use language created by others. Without language their mental power would not grow.

We have to admit that we owe principal knowledge over the least to the fact of living in human society. The individual if left alone from birth would remain primitive. They are superior to beast, because they live in human society. An individual life left alone from birth would grow utterly beast like. So human society and not individuality guides man’s material and spiritual existence.

Fair Draft: Man is a Social Animal

Being social animals, human beings have their actions and desires bound up with society. In the matter of food, clothes, knowledge and belief we are interdependent. We eat food, wear clothes, live in houses that others have produced or made. We use language created by others. Without language, their mental power would not grow. An individual life left alone from birth would grow utterly beast-like. So human society and not individuality guides man’s material and spiritual existence.

No. of words in the summary: 77

[OR]

Notes
Title: Man is a Social Animal
Survey:
lives & efforts
our actions & desires – bound up

Practices:
Eat food – wear clothes – live in houses – made by others
Lang – learnt 4m others – for mental power

Status:
Indiv. if left alone – be primitive
The individual – much in virtue
member A human community – directs mat. & spiritual existence.

Abbreviations used: & – and; A – of; lang. – language; indiv. – individual; 4m – from; mat. – material

Question 45.
Write a letter to the manager of M/S Santiago and Co, placing an order for 25 high speed ceiling fans of different sizes. You, David/Delshya is the Finance Director of HCL company.
Answer:
From
Mr. David
Finance Head
HCL – Rajakilpakkam
Maduravoyal
26th March, 2020

To
Messrs. Santiago and Co.
3, Rutt Market
Chennai

Sir,

Reg: Supply of High Speed Ceiling Fans

Please send by road transport the following Pavlo High Speed Ceiling fans so as to reach us before 10th April, 2020 at the rates as mentioned I your catalogue – cum – price list for 2020-2021 with a trade discount of 15% on the total amount of the invoice. We would like to place on order the following:

• 10 Pavlo High Speed Ceiling fans 58 inches size
• 05 Pavlo High Speed Ceiling fans 48 inches size
• 10 Pavlo High Speed Ceiling fans 36 inches size

Please ensure that the packing is without any discrepancies. Kindly note that the goods with manufacturing defects or those damaged in transit will be returned at your cost. A cheque bearing number 324657 for Rs. 10,000/- dated 30th March, 2020 as advance payment is enclosed herewith. The balance amount will be paid within a fortnight after receipt of goods. Thanking you in advance for your delivery of goods without any delay.

Yours sincerely,
Mr. David – Finance Director
(for) HCL – Rajakilpakam

Address on the envelope:
To
Messrs. Santiago and Co.
3, Rutt Market
Chennai

[OR]

Write a paragraph of 150 words on “Hazards Of Reckless Driving”.
Answer:
Hazards Of Reckless Driving

Careless driving is one of the leading causes of accidents. When a driver fails to drive with due. care, it can cause serious harm to others sharing the road. I had a bitter experience of such reckless driving last month while returning from GGHS School, which is just a kilometre away from my house. As I was returning home around 5.30 p.m., after Math coaching class, I heard some screaming behind me and hence just turned to see what the sound was about.

The very next second, I was knocked down by a speeding motorcycle. I had a hairline crack on my right ankle and bruises on my right arm. I was really lucky that I did not have major issues. However, I was in a state of severe shock for more than a week and I dreaded stepping out on the road. There should be severe actions taken against those who violate traffic rules.

Question 46.
Spot the errors and rewrite the sentences correctly.
(а) Neither Ravi nor Rani have failed.
(b) The Collection ‘Fragrant Flowers’ are quite interesting.
(c) The distance between Chennai to Trichy is more than 300 Kins.
(d) The scissors is missing.
(e) We are living at Chennai.
Answer:
(a) Neither Ravi nor Rani has failed.
(b) The Collection ‘Fragrant Flowers’ is quite interesting.
(c) The distance from Chennai to Trichy is more than 300 Kms.
(d) The scissors are missing.
(e) We are living in Chennai.

[OR]

Fill in the blanks correctly.
(a) My cat was crazily chasing a squirrel while I ………….. (red/read) a fairy ………….. (tale/tail) to my children.
(b) That looks delicious, and I am so hungry! ………….. I have some? (Use a modal in the given blank.)
(c) I have worked too long! I ………….. take a break! (use a semi-modal)
(d) They (go) to take a cruise next summer. (use a proper tense)
Answer:
(a) read/tále (b) May (c) need to (d) are going

Question 47.
Identify each of the following sentences with the fields given below;
(a) French actress Mary’s clothing was designed by her friend Yas for her next project.
(b) In the world’s largest open-air theatre, stories of Krishna and Kansa area magically retold,
(c) Technology develops machines that can substitute for humans and replicate human actions.
(d) A normal bulb uses almost 80% energy to create heat and only 20% for production of light.
(e) A tropical diet is based on fruits and vegetables, while a polar diet rely on meat and fish.
[Robotics; Cuisine; Movie; Electrodynamics; Entertainment]
Answer:
(а) Movie (b) Entertainment (c) Robotics (d) Electrodynamics (e) Cuisine

[OR]

Read the following passage and answer the questions in your own words.
Answer:
A long time ago there lived a monster called the sphinx. She had the head of a woman, the body of a lion and the wings of a big bird. Her eyes were so fierce that nobody dared to look at her face. The sphinx sat on a cliff outside the city of Thebes. When a man passed by her, she would ask him a riddle. The man had to give the right answer, or the sphinx would eat him up. The riddle was so difficult that no one could answer it.

Many men lost their lives and people were afraid to come out of their houses. Then one day a clever man wanted to answer the sphinx. His name was Oedipus and he was not afraid of the sphinx. The sphinx stopped and asked him a riddle “what walks on four legs in the morning, on two legs at noon and on three legs in the evening?”

Oedipus said that it was easy, “you try and answer it!” roared the sphinx. Oedipus said, “The answer is man walks on four legs in his childhood, on two legs when grown up and on three legs during old age”. Hearing the right answer the sphinx was disappointed and very angry. She jumped off the cliff and ended her life.

Questions:
a. How did the sphinx look like?
b. What would the sphinx do if a man failed to give the right answer to her riddle?
c. Why was the sphinx angry?
d. What is the ‘third leg’ of man in his old age?
e. What is the most suitable title to the passage?
Answers:
(a) The sphinx looked like a monster with the head of a woman, the body of a lion and the wings of a big bird.
(b) The sphinx would eat up the man if he failed to give the right answer to her riddle.
(c) Hearing the right answer to her riddle from Oedipus, the sphinx was disappointed and very angry
(d) The third leg is invariably the walking stick the old man will be using in his old age.
(e) The title could be ‘Sphinxs’ Riddles’.

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TN State Board 12th Commerce Model Question Paper 4 English Medium

Instructions:

1. The question paper comprises of four parts.
2. You are to attempt all the parts. An internal choice of questions is provided wherever applicable.
3. All questions of Part I, II. III and IV are to be attempted separately.
4. Question numbers 1 to 20 in Part I are Multiple Choice Questions of one mark each. These are to be answered by choosing the most suitable answer from the given four alternatives and writing the option code and the corresponding answer.
5. Question numbers 21 to 30 in Part II are two-mark questions. These are to be answered in about 50 words.
6. Question numbers 31 to 40 in Part III are three-mark questions. These are to be answered in about 150 words.
7. Question numbers 41 to 47 in Part IV are five-mark questions. These are to be answered in about 250 words. Draw diagrams wherever necessary.

Time: 3 Hours
Max Marks: 90

Part -I

Choose the correct answer. Answer all the questions: [20 x 1 = 20]

Question 1.
Drucker stresses jobs of management.
(a) three
(b) two
(c) four
(d) Six
Answer:
(a) three

Question 2.
Choose the odd one out?
(a) Directing
(b) Motivating
(c) Innovation
(d) Controlling
Answer:
(c) Innovation

Question 3.
…………… harmonises the goal of an individual with the organisation’s goal.
(a) MBO
(b) MBE
(c) MBA
(d) MBM
Answer:
(a) MBO

Question 4.
Indian organised financial system consist of sectors.
(a) Two
(b) Four
(c) Three
(d) Six
Answer:
(b) Four

Question 5.
Capital market otherwise called as …………..
(a) Securities market
(b) Share market
(c) Debenture market
(d) Money market
Answer:
(a) Securities market

Question 6.
……………………. deals with the financial assets and securities whose maturity period does not exceed one year.
(a) Money market
(b) Capital market
(c) Stock exchange
(d) Government bonds
Answer:
(a) Money market

Question 7.
The consumer is to be protected against any ……………..
(a) unfair practices of trade
(b) family functions
(c) profit making firm
(d) loss in business
Answer:
(a) unfair practices of trade

Question 8.
The National Commission should have members.
(a) 3
(b) 4
(c) 5
(d) 6
Answer:
(d) 6

Question 9.
………………. is the latest outcome of liberalization.
(a) Privatisation
(b) Globalisation
(c) Foreign collaboration
(d) None of these
Answer:
(c) Foreign collaboration

Question 10.
A bill of exchange drawn on a specified banker is ……………
(a) promissory note
(b) cheque
(c) hundi
(d) share
Answer:
(b) cheque

Question 11.
The entrepreneurs classified on the basis of types of business are …………….
(i) Industrial entrepreneur
(ii) Technical entrepreneur
(iii) Professional entrepreneur
(iv) Business entrepreneur
(a) (i) and (iii)
(b) (i) and (iv)
(c) (ii) and (iii)
(d) (ii) and (iv)
Answer:
(b) (i) and (iv)

Question 12.
Board meetings to be conducted minimum times in a year.
(a) 2
(b) 3
(c) 4
(d) 5
Answer:
(c) 4

Question 13.
A public company shall have a minimum of ……………. directors.
(a) Twelve
(b) Seven
(c) Three
(d) Two
Answer:
(c) Three

Question 14.
Which of the following types of shares are issued by a company to rains capital from the existing shareholders?
(a) Equity shares
(b) Rights shares
(c) Preference shares
(d) Bonus shares
Answer:
(b) Rights shares

Question 15
should cover aspects like sources of finance, technical know-how, source of labours and raw material, market potential and profitability.
(a) Technical Report
(b) Finance Report
(c) Project Report
(d) Progress Report
Answer:
(c) Project Report

Question 16.
Find the odd one out is context of Trading Entrepreneur.
(a) Selling
(b) Commission
(c) Buying
(d) Manufacturing
Answer:
(d) Manufacturing

Question 17.
Which of the below is not classified into managerial function.
(a) Planning
(b) Marketing
(c) Organising
(d) Controlling
Answer:
(c) Organising

Question 18.
Section 6 of Negotiable Instruments Act 1881 deals with ……………
(a) Promissory Note
(b) Bills of exchange
(c) Cheque
(d) None of the above
Answer:
(c) Cheque

Question 19.
……………… results from the removal of barriers between national economics to encourage the flow of goods, services, capital and labour.
(a) privatisation
(b) Liberalisation
(c) Globalisation
(d) Foreign Trade
Answer:
(c) Globalisation

Question 20.
The state commission can entertain complaints where the value of the goods or services and the compensation, if any claimed exceed.
(a) ₹ 2 lakhs but does not exceed ₹ 5 lakhs
(b) ₹ 20 lakhs but does not exceed ₹ 1 crore
(c) ₹3 lakhs but does not exceed ₹ 5 lakhs
(d) ₹ 4 lakhs but does not exceed ₹ 20 lakhs
Answer:
(d) ₹ 4 lakhs but does not exceed ₹ 20 lakhs

PART – II

Answer any seven in which Question No.30 is compulsory. [7 x 2 = 14]

Question 21.
State the meaning of Authority.
Answer:
Authority means the right of a superior to give the order to his subordinates. This is the issue of commands followed responsibility for their consequences.

Question 22.
How is price decided in a secondary market?
Answer:
Financial markets allow for the determination of the price of the traded financial asset through the interaction of buyers and sellers. They provide a signal for the allocation of funds in the economy, based on the demand and supply, through the mechanism called price discovery processes.

Question 23.
What is meant by Remiser?
Answer:
Remiser is an agent of a member of a stock exchange. He obtains business for his principal i.e. the member.

Question 24.
What is Human Resource Management ?
Answer:
Human Resource Management is a function of management concerned with hiring, motivating and maintaining people in an organisation. It focuses on people in an organisation.

Question 25.
Define Marketer.
Answer:
“A person whose duties include the identification of the goods and services desired by a set of consumers, as well as the marketing of those goods and services on behalf of a company”.

Question 26.
What is Caveat Emptor?
Answer:
‘Caveat emptor’ is a Latin term that means “let the buyer beware.” Similar to the phrase “sold as is,” this term means that the buyer assumes the risk that a product fails to meet expectations or have defects.

Question 27.
Expand VUCA.
Answer:
VUCA – volatility, uncertainty, complexity and ambiguity.

Question 28.
What is meant by goods?
Answer:
The term goods mean every kind of movable property other than actionable claim and money.

Question 29.
List down the managerial functions of entrepreneurs.
Answer:

• Planning
• Organising
• Directing
• Controlling
• Coordination

Question 30.
What do you mean by Equity Share?
Answer:
The share of a company which do not have any preferential rights with regard to dividend and repayment of share capital at the time of liquidation of a company, is called as equity share or ordinary share.

Part – III

Answer any seven in which question No. 40 is compulsory. [7 x 3 = 21]

Question 31.
What are the principles of Taylor?
Answer:
Principles of scientific management propounded by Taylor are:

• Science, Not Rule of Thumb
• Harmony, Not Discord
• Mental Revolution
• Cooperation, Not individualism
• Development of each and every person to his or her greatest efficiency and prosperity.

Question 32.
Write a note on Secondary Market.
Answer:
Secondary Market is the market for securities that are already issued. Stock Exchange is an important institution in the secondary market.

Question 33.
Explain National Stock Market System. (NSMS)
Answer:
National stock market system was advocated by the High Powered Group. It is headed by Shri. Pherwani (popularly known as Pherwani Committee). At present the National Stock Market comprises the following:

• National Stock Exchange of India Limited (NSE)
• Stock Holding Corporation of India Limited (SHCIL)
• Securities Trading Corporation of India (STCI)

Question 34.
Marketer is an innovator? Do you agree?
Answer:
Marketer seeks to distinguish his products/services by adding additional features or functionalities to the existing product, modifying the pricing structure, introducing new delivery pattern, creating new business models, introducing change in production process and so on.

Question 35.
What is meant by artificial scarcity?
Answer:
There are certain situations where the shop-keepers put up the board ‘No Stock” in front of their shops, even though there is plenty of stock in the store. In such situations consumers who are desperate to buy such goods have to pay hefty price to buy those goods and thus earning more profit unconscientiously.

Question 36.
State the framework of Corporate Governance in India.
Answer:
The Indian Corporate Governance framework requires listed companies

• To have independent directors on the board; At least one third of the directors have to be independent directors.
• To have at least one independent woman director,
• To disclose all deals and payments to related parties.
• To disclose details of managerial compensation.

Question 37.
Discuss the implied conditions and warranties in sale of goods contract.
Answer:
In every contract of sale, there are certain expressed and implied conditions and warranties. The term implied conditions means conditions which can be inferred from or guessed from the context of the contract.Following are the implied conditions:

• Conditions as to Title
• Conditions as to Description
• Sale by Sample
• Conditions as to Quality or Fitness
• Conditions as to Merchantability
• Condition as to Wholesomeness
• Condition Implied by Trade Usage Following are the implied warranties:
• Quiet Possession
• Free from Any Encumbrances
• Warranty in the case of Dangerous Goods

Question 38.
List the commercial functions of Entrepreneur and explain them shortly.
Answer:
Commercial Functions of Entrepreneur:
Production or Manufacturing: Under production function, entrepreneur has to take decision relating to selection of factory site, design and layout, type of products to be manufactured, research and development, product design, etc.

Marketing: Entrepreneur has to carry out following functions pertaining to marketing aspect namely consumer research, product planning and development, standardisation, packaging, pricing, warehousing, distribution, promotion etc.

Accounting: Entrepreneur has to arrange to prepare trading and profit and loss account in order to know the profit or loss incurred out of operation of the business and prepare balance sheet to know the financial status of business at a particular day.

Finance: In the sphere of financial function, an entrepreneur has to take decisions like choosing the right type of financing, framipg the best dividend policy, acquiring of funds, efficiently managing fixed and current assets, maximising shareholders wealth and investing of funds efficiently and effectively.

Human Resource Management: Entrepreneur has to estimate the manpower needs of the enterprise and accordingly decide the size of manpower required for various slots of organisational structure.

Question 39.
What is issue of shares at discount? What conditions should be fulfilled?
Answer:
When the shares are issued at a price below the face value they are said to be issued at a discount. For example, a share having the face value of Rs 10 is issued at Rs 8. The companies act 2013, prohibits the issue of shares at discount (Section 53), except sweat Equity share.

Question 40.
What do you understand by ‘Poll’?
Answer:
Poll means tendering or offering vote by ballot to a specially appointed officer, called the polling officer. Under the Companies Act, poll means exercising voting right in proportion to shareholder’s contribution to the paid-up capital of a limited company having a share capital.

Part – IV

Answer all the following questions. [7 x 5 = 35]

Question 41.
(a) Discuss the implications of span of management.
Answer:
The Span of Management has two implications:
(i) Influences the complexities of the individual manager’s job.
(ii) Determine the shape or configuration of the Organisation.
The span of management is related to the horizontal levels of the organisation structure. There is a wide and a narrow span of management. With the wider, span, there will be less hierarchical levels, and thus, the organisational structure would be flatter. Whereas, with the narrow span, the hierarchical levels increases, hence the organisational structure would be tall.

• Both these organisational structures have their advantages and the disadvantages. But however the tall organisational structure imposes more challenges.
• Since the span is narrow, which means less number of subordinates under one superior, requires more managers to be employed in the organisation. Thus, it would be very expensive in terms of the salaries to be paid to each senior.
• With more levels in the hierarchy, the communication suffers drastically. It takes a lot of time to reach the appropriate points, and hence the actions get delayed.
• Lack of coordination and control because the operating staff is far away from the top management.

[OR]

(b) What are the functions of Financial Markets?
Answer:
Intermediary Functions
(i) Transfer of Resources: Financial markets facilitate the transfer of real economic resource from lenders to ultimate borrowers.

(ii) Enhancing Income: Financial markets allow lenders earn interest/dividend on their surplus
investible funds and thus contributing to the enhancement of the individual and the national income.

(iiI) Productive Usage: Financial markets allow for the productive use of the funds borrowed and thus enhancing the income and the gross national production.

(iv) Capital Formation: Financial markets provide a channel through which new savings flow to aid capital formation of a country.

(v) Price Determination: Financial markets allow for the determination of the price of the traded financial asset through the interaction of buyers and sellers.

(vi) Sale Mechanism: Financial market provides a mechanism for selling of a financial
asset by an investor so as to offer the benefits of marketability and liquidity of such assets.

(vii) Information: The activities of the participants in the financial market result in the generation and the consequent dissemination of information to the various segments of the markets, so as to reduce the cost of transaction of financial assets.

Financial Functions

• Providing the borrowers with funds so as to enable them to carry out their investment plans.
• Providing the lenders with earning assets so as to enable them to earn wealth by deploying the assets in productive ventures.
• Providing liquidity in the market so as to facilitate trading of funds

Question 42.
(a) Explain the various types of New Financial Institutions.
Answer:
(i) Venture Fund Institutions: Venture capital financing is a form of equity financing designed especially for funding new and innovative project ideas. Venture capital funds bring into force the hi-technology projects which are converted into commercial  production.

(ii) Mutual Funds: Financial institutions that provide facilities for channeling savings of small investors into avenues of productive investments are called ‘Mutual Funds’.

(iii) Factoring Institutions: “Factoring” is an arrangement whereby a financial institution provides financial accommodation on the basis of assignment/sale of account receivables.

(iv) Over the Counter Exchange of India (OTCEI): The OTCEI was set up by a premier
financial institution to allow the trading of securities across the electronic counters throughout the country.

(v) National Stock Exchange of India Limited (NSEI): NSEI was established in 1992 to function as a model stock exchange. The Exchange aims at providing the advantage of nation-wide electronic screen based “scripless” and “floorless” trading system in securities.

(vi) National Clearance and Depository System (NCDS): Under the scripless trading system, settlement of transactions relating to securities takes place through a book entry.

(vii) National Securities Depositories Limited: The NSDL was set up in the year 1996 for achieving a time bound dematerialization as well as rematerialization of shares.

(viii) Stock Holding Corporation of India Limited (SHCIL): Stock Holding Corporation of India Limited (SHCIL) aims at serving as a central securities depository in respect of transactions on stock exchanges. The Corporation also takes up the administration of clearing functions at a national level.

[OR]

(b) What are the features of Government Securities?
Answer:
(i) Agencies: Government securities are issued by agencies such as Central Government, State Governments, semi-government authorities like local Government authorities.
(ii) RBI Special Role: RBI takes a special and an active role in the purchase and sale of these securities as part of its monetary management exercise.
(iii) Nature of Securities: Securities offer a safe avenue of investment through guaranteed payment of interest and repayment of principal by the Government.
(iv) Liquidity Profile: The liquidity profile of gilt-edged securities varies. Accordingly liquidity profile of securities issued by Central Government is high.
(v) Tax Rebate: A striking feature of these securities is that they offer wide-range of tax incentives to investors.

(vi) Market: As each sale and purchase has to be negotiated separately, the Gilt-Edged Market is an Over-The-Counter Market.
(vii) Forms: The securities of Central and State Government take such forms as inscribed stock or stock certificate, promissory note and bearer bond.
(viii) Participants: The participants in Government securities market include the Government sector comprising Central and State Governments
(ix) Trading: Small and less active, banks and corporate holders who purchase and sell Government securities on the stock exchanges participate in trading.
(x) Issue Mechanism: The Public Debt Office (PDO) of the RBI undertakes to issue government securities.
(xi) Issue opening: A notification for the issue of the securities is made a few days before the public subscription is open.
(xii) Grooming Gradual: It is the acquisition of securities nearing maturity through the stock exchanges by the RBI.
(xiii) Switching: It is the purchase of one security against the sale of another security carried out by the RBI in the secondary market as part of its open market operations.
(xiv) Auctioning: A method of trading whereby merchants bid against one another and where the securities are sold to the highest bidder.

Question 43.
(a) Distinguish between Stock Exchange and Commodity Exchange.
Differences between Stock Exchange and Commodity Exchange.

[OR]

(b) Differentiate HR from HRM.

Question 44.
(a) Explain the important methods of interview.
Answer:
Interview means a face to face interaction between the interviewer and interviewee.
Interview may be of various types:-

• Preliminary Interview: It is conducted to know the general suitability of the candidates who have applied for the job.
• Structured Interview: In this method, a series of questions is to be asked by the interviewer. The questions may be pre-prepared.
• In depth Interview: This interview is conducted to test the level of knowledge of the interviewee in a particular field.
• Panel Interview: Where a group of people interview the candidate. The panel usually comprises the chair person, subject expert, psychological experts and so on.
• Stress Interview: This type of interview is conducted to test the temperament and emotional balance of the candidate.
• Online Interview: Due to tremendous growth in information and communication technology, interviews are conducted by means of internet via Skype, Google duo, Whatsapp.

[OR]

(b) What is your contribution to promote the market in the modern society?
Answer:
Market is a place where buyers and sellers gather for purchase and sale.
Market may be of Local market, national market and international or Global market.
To develop and promote the market the following are needed:

• Eligible and satisfied and customer is needed.
• Quality and durable goods are to be marketed.
• Recent trends like E-marketing, online marketing are to be encouraged.
• After sales service are to be provided to durable goods.
• Customers are to be financed for buying costly articles.
• New Innovations and marketing research are to be introduced to develop the market.

Question 45.
(a) Discuss any two new methods of marketing with its advantages.
Answer:
Rural Marketing: Rural marketing is a process of developing pricing, promoting and distributing rural specific goods and serv ices leading to exchange with rural customers.There is inflow of goods into rural markets for production and consumption and there is also outflow of products to urban areas.
The rural to urban flow consists of agricultural products like rice, wheat and sugar etc.

Service Marketing: Service marketing is a special branch of marketing. It denotes the processing of selling service goods like telecommunication, banking, insurance, healthcare, tourism and professional services. The service products are mostly intangible. The unique feature of services marketing warrant different strategies compared with the marketing of physical goods.

[OR]

(b) Write about five important consumer legislations.
Answer:
To protect the consumers from the unfair traders, the government passed various legislative Acts – They are follows:

• The Indian Contract Act, 1982 was passed to bind the people on the promise made in the contract.
•  The Essential Commodities Act, 1955 protects the consumers against artificial shortages created by the sellers by hoarding the goods.
• The Prevention of Food Adulteration Act, 1954 checks the adulteration of food articles and ensures purity of goods supplied.
•  Weights and Measures Act, 1958 protects the consumer against malpractices of underweight dr under measurement.

Question 46.
(a) Explain the term District Forum and explain the functions of District Forum.
Answer:
As per the Consumer Protection Act 1986, a district forum is established in each and every district to solve the problems in the concerned district. Present or Retired district judge is the president of District forum

Functions:

• The complaints relating to the district can be solved by district forum.
• Compensation that can be claimed is less than Rs. 20 lakhs.
• Sometimes the district forum also may pass orders against traders.

[OR]

(b) Distinguish between Condition and Warranty.

Question 47.
(a) Explain the different kinds of endorsements.
Answer:
When the person signs on the back of the instrument to transfer his interest, it is known as endorsement. The endorsement are of various types:

(i) Blank or general endorsement : When the endorser puts his mere signature on the back of an instrument without mentioning the name of the person to whom the endorsement is made, it is called Blank Endorsement

(ii) Endorsement in full or special endorsement: If the endorser, in addition to his signature, mentions the name of the person to whom it is endorsed, is known as endorsement in full or special endorsement.

(iii) Conditional endorsement: When the endorser of a negotiable instrument makes his liability dependent upon the happening of an event which may or may not happen, it is called conditional endorsement.

(iv) Restrictive endorsement : When an endorsement restricts or prohibits further negotiability of the instrument, it is, called Restrictive Endorsement.

(v) Partial Endorsement :Where the endorsement seeks to transfer only a part of the amount payable under the instrument, the endorsement is called Partial Endorsement.

[OR]

(b) Write the difference between Share Certificate and Share Warrant.
Answer: