Prasanna

Students can download Maths Chapter 7 Mensuration Ex 7.3 Questions and Answers, Notes, Samacheer Kalvi 10th Maths Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Maths Solutions Chapter 7 Mensuration Ex 7.3

Question 1.
A vessel is in the form of a hemispherical bowl mounted by a hollow cylinder. The diameter is 14 cm and the height of the vessel is 13 cm. Find the capacity of the vessel.
Answer:
Radius of a hemisphere = Radius of the cylinder

Question 2.
Nathan, an engineering student was asked to make a model shaped like a cylinder with two cones attached at its two ends. The diameter of the model is 3 cm and its length is 12 cm. If each cone has a height of 2 cm, find the volume of the model that Nathan made.
Answer:
Radius of the cone = Radius of the cylinder

r = \(\frac{3}{2}\) cm
Height of the cone (H) = 2 cm
Height of the cylinder (h) = 12 – (2 + 2) cm = 8 cm
Volume of the model = Volume of the cylinder + Volume of 2 cones

Question 3.
From a solid cylinder whose height is 2.4 cm and the diameter 1.4 cm, a cone of the same height and same diameter is carved out. Find the volume of the remaining solid to the nearest cm³.
Answer:
Radius of a cylinder = Radius of a cone r = 0.7 cm
Height of a cylinder = Height of a cone (h) = 2.4 cm

Volume of the remaining solid = Volume of the cylinder – Volume of a cone

Volume of the remaining soild = 2.46 cm³

Question 4.
A solid consisting of a right circular cone of height 12 cm and radius 6 cm standing on a hemisphere of radius 6 cm is placed upright in a right circular cylinder full of water such that it touches the bottom. Find the volume of the water displaced out of the cylinder, if the radius of the cylinder is 6 cm and height is 18 cm.

Answer:
Radius of a cone = Radius of a hemisphere = Radius of a cylinder
r = 6 cm
Height of a cone (h) = 12 cm
Volume of the water displaced = Volume of the solid inside = Volume of the cone + Volume of the hemisphere

Volume of water displaced = 905. 14 cm³.

Question 5.
A capsule is in the shape of a cylinder with two hemispheres stuck to each of its ends. If the length of the entire capsule is 12 mm and the diameter of the capsule is 3 mm, how much medicine it can hold?
Answer:
Radius of a hemisphere = Radius of a Cylinder

r = \(\frac{3}{2}\) mm = 1.5 mm
Height of the cylinderical portion = 12 mm – (1.5 mm + 1.5 mm) = (12 – 3) mm = 9 mm
Volume of the capsule

Volume of the capsule = 77.8 cu. mm

Question 6.
As shown in figure a cubical block of side 7 cm is surmounted by a hemisphere. Find the surface area of the solid.

Answer:
Side of a cube (a) = 7 cm
Radius of a hemisphere (r) = \(\frac{7}{2}\) cm
Surface area of the solid = T.S.A of the cube + C.S.A of the hemisphere – Area of the base of the hemisphere

Question 7.
A right circular cylinder just encloses a sphere of radius r units. Calculate
(i) the surface area of the sphere
(ii) the curved surface area of the cylinder
(iii) the ratio of the areas obtained in (i) and (ii).
Answer:
(i) Surface area of sphere = 4πr² sq. units

Question 8.
A shuttlecock used for playing badminton has the shape of a frustum of a cone is mounted on a hemisphere. The diameters of the frustum are 5 cm and 2 cm. The height of the entire shuttlecock is 7 cm. Find its external surface area.
Answer:

Students can Download Tamil Nadu 11th Chemistry Model Question Paper 2 English Medium Pdf, Tamil Nadu 11th Chemistry 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 11th Chemistry Model Question Paper 2 English Medium

General 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 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
5. Question numbers 16 to 24 in Part II are two-mark questions. These are to be answered in about one or two sentences.
6. Question numbers 25 to 33 in Part III are three-mark questions. These are to be answered in about three to five short sentences.
7. Question numbers 34 to 38 in Part IV are five-mark questions. These are to be answered in detail Draw diagrams wherever necessary.

Time: 2:30 Hours
Maximum Marks: 70

PART – I

Answer all the Questions: [15 × 1 = 15]
Choose the most suitable answer from the given four alternatives.

Question 1.
An element X has the following isotopic composition ²⁰⁰X = 90 %, ¹⁰⁰X = 8 % and ²⁰²X = 2 %.
The weighted average atomic mass of the element X is closest to ………………………….
(a) 201 u
(b) 202 u
(c) 199 u
(d) 200 u
\(\frac { (200\times 90)+(199\times 18)+(202\times 2) }{ 100 } \)
= 199.96 = 200 u
Answer:
(d) 200 u

Question 2.
Which of the following is not used in writing electronic configuration of an atom?
(a) Aufbau principle
(b) Hund’s rule
(c) Pauli’s exclusion principle
(d) Heisenberg’s uncertainty principle
Answer:
(d) Heisenberg’s uncertainty principle

Question 3.
Assertion (A): Cr with electronic configuration [Ar]3d⁵ 4s¹ is more stable than [Ar] 3d⁴ 4s².
Reason (R): Half filled orbitals have been found to have extra stability than partially filled orbitals.
(a) A and R are correct and R is the correct explanation of A.
(b) A and R are correct but R is not the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) A and R are correct and R is the correct explanation of A.

Question 4.
The type of H-bonding present in ortho nitro phenol and p-nitro phenol are respectively ……………………..
(a) Inter molecular H-bonding and intra molecular H – bonding
(b) Intra molecular H-bonding and inter molecular H – bonding
(c) Intra molecular H – bonding and no H – bonding
(d) Intra molecular H – bonding and intra molecular H – bonding

Answer:
(b) Intra molecular H-bonding and inter molecular H – bonding

Question 5.
Match the following:

Answer:

Question 6.
Which of the following is the correct expression for the equation of state of van der Waals gas?
(a) \(\left(P+\frac{a}{n^{2} V^{2}}\right)\) (V – nb) = nRT
(b) \(\left(P+\frac{n a}{n^{2} V^{2}}\right)\) (V – nb) = nRT
(c) \(\left(P+\frac{a n^{2}}{V^{2}}\right)\) (V – nb) = nRT
(d) \(\left(P+\frac{n^{2} a^{2}}{V^{2}}\right)\) (V – nb) = nRT
Answer:
(c) \(\left(P+\frac{a n^{2}}{V^{2}}\right)\) (V – nb) = nRT

Question 7.
In a reversible process, the change in entropy of the universe is ………………………
(a) > 0
(b) >0
(c) <0
(d) = 0
Answer:
(d) = 0

Question 8.
Which of the following is not a general characteristic of equilibrium involving physical process?
(a) Equilibrium is possible only in a closed system at a given temperature
(b) The opposing processes occur at the same rate and there is a dynamic but stable condition
(c) All the physical processes stop at equilibrium
(d) All measurable properties of the system remains constant
Solution:
Correct statement: Physical processes occurs at the same rate at equilibrium.
Answer:
(c) All the physical processes stop at equilibrium

Question 9.
Stomach acid, a dilute solution of HCl can be neutralised by reaction with Aluminium hydroxide
Al(OH)₃ + 3HCl(aq) → AlCl₃ + 3H₂O
How many millilitres of 0.1 M Al(OH)₃ solution are needed to neutralise 21 mL of 0.1 M HCl?
(a) 14 mL
(b) 7 mL
(c) 21 mL
(d) None of these
Solution:
M₁ × V = M₂ × V₂
∵ 0.1 M Al(OH)₃ gives 3 × 0.1 = 0.3 M OH^– ions
0.3 × V₁ = 0.1 × 21
V₁ = \(\frac{0.1×21}{0.3}\) = 7 ml
Answer:
(b) 7 mL

Question 10.
Shape and hybridisation of IF₅ are ……………………..
(a) Trigonal bipyramidal, sp³d²
(b) Trigonal bipyramidal, sp³d
(c) Square pyramidal, sp³d²
(d) Octahedral, sp³d²
Solution:
IF₅ – 5 bond pair + 1 lone pair
∴ hybridisation sp³d²

Answer:
(c) Square pyramidal, sp³d²

Question 11.
Consider the following statements:

1. It is not possible for the carbon to form either C⁴⁺ (or) C^4- ions.
2. Carbon can form ionic bonds.
3. In compounds of carbon, it form covalent bonds.

Which of the above statement is/are not correct?
(a) (I) and (II)
(b) (III) only
(c) (I) only
(d) (II) only
Answer:
(d) (II) only

Question 12.
For the following reactions
(A) CH₃CH₂CH₂Br + KOH → CH₃-CH + KBr + H₂O
(B) (CH₃)₃CBr + KOH → (CH₃)₃ COH + KBr
(C)
Which of the following statement is correct?
(a) (A) is elimination, (B) and (G) are substitution
(b) (A) is substitution, (B) and (C) are elimination
(c) (A) and (B) are elimination and (C) is addition reaction
(d) (A) is elimination, B is substitution and (C) is addition reaction.
Answer:
(d) (A) is elimination, B is substitution and (C) is addition reaction.

Question 13.
Which of the following compound used for metal cleaning solvent?
(a) Methylene chloride
(b) Methyl chloride
(c) Chloroform
(d) Ethane
Answer:
(a) Methylene chloride

Question 14.
The number of possible isomers of C₆H₁₂ is ……………………..
(a) 2
(b) 3
(c) 5
(d) 6
Answer:
(c) 5

Question 15.
Ozone layer is depleted by the reactive ……………………..
(a) Hydrogen atom
(b) Oxygen atom
(c) Fluorine atom
(d) Chlorine atom
Answer:
(d) Chlorine atom

PART – II

Answer any six questions in which question No. 19 is compulsory. [6 × 2 = 12]

Question 16.
Calculate the average atomic mass of naturally occurring magnesium using the following data?

Answer:
Solution: Isotopes of Mg.
Atomic mass = Mg²⁴ = 23.99 × 78.99/100 = 18.95
Atomic mass = Mg²⁶ = 24.99 × 10/100 = 2.499
Atomic mass = Mg²⁵ = 25.98 × 11.01/100 = 2,860
Average Atomic mass = 24.309
Average atomic mass of Mg = 24.309

Question 17.
What are quantum numbers?
Answer:

1. The electron in an atom can be characterized by a set of four quantum numbers, namely – principal quantum number (n), azimuthal quantum number (l), magnetic quantum number (m) and spin quantum number (s).
2. When Schrodinger equation is solved for a wave function φ, the solution contains the first three quantum numbers n, 1 and m.
3. The fourth quantum number arises due to the spinning of the electron about its own axis.

Question 18.
How 2-ethylanthraquinone helps to prepare hydrogen peroxide?
Answer:
On an industrial scale, hydrogen peroxide is prepared by auto oxidation of 2-alkyl anthraquinol.

Question 19.
Calculate the pressure exerted by 2 moles of sulphur hexafluoride in a steel vessel of volume 6 dm³ at 70°C assuming it is an ideal gas?
Answer:
We will use the ideal gas equation for this calculation as below:
P = \(\frac{nRT}{V}\) = image 7 = 9.39 atm.

Question 20.
What are the important features of lattice enthalpy?
Answer:

1. Higher lattice energy shows greater electrostatic attraction and therefore a stronger bond in the solid.
2. The lattice enthalpy is greater for ions of higher charge and smaller radii.

Question 21.
What are aqueous and non-aqueous solution? Give example?
Answer:

1. If the solute is dissolved in the solvent water, the resultant solution is called as an aqueous solution, e.g., salt in water.
2. If the solute is dissolved in the solvent other than water such as benzene, ether, CCl₄ etc, the resultant solution is called a non aqueous solution, e.g., Br₂ in CCl₄.

Question 22.
What is bond enthalpy? How they relate with bond strength?
Answer:
The bond enthalpy is defined as the minimum amount of energy required to break one mole of a particular bond in molecules in their gaseous state. Larger the bond enthalpy stronger will be the bond.

Question 23.
What is triad system? Give example?
Answer:
(I) In this system hydrogen atom oscillates between three polyvalent atoms. It involves 1, 3 – migration of hydrogen atom from one polyvalent atom to other with in the molecule

(II) The most important type of triad system is keto-enol tautomerism and the two groups of tautomers are keto form and enol form.

(III)

Question 24.
What is stone leprosy? How is it formed?
Answer:

1. The attack on, the marble of buildings by acid rain is called stone leprosy.
2. Acid rain causes extensive damage to buildings made up of marble.

CaCO + H₂SO₄ → CaSO₄ + H₂O + CO₂↑

PART – III

Answer any six questions in which question No. 26 is compulsory. [6 × 3 = 18]

Question 25.
Calculate the equivalent mass of hydrated ferrous sulphate?
Answer:
Hydrated ferrous sulphate = FeSO₄.7H₂O
Ferrous sulphate – Reducing agent
Ferrous sulphate reacts with an oxidising agent in acid medium according to the equation.

16 parts by mass of oxygen oxidised 304 g of FeSO₄.
8 parts by mass of oxygen will oxidise \(\frac{304}{16}\) × 8 parts by mass of FeSO₄ = 152
Equivalent mass of Ferrous sulphate (Anhydrous) = 152
Equivalent mass of crystalline Ferrous sulphate FeSO₄.7H₂O = 152 + 126 = 278

Question 26.
Calculate the uncertainty in position of an electron, if ∆v = 0.1% and v = 2.2 × 10⁶ ms^-1.
Answer:
Mass of an electron = m = 9.1 × 10^-31 kg.
∆v = Uncertainty in velocity = \(\frac{0.1}{100}\) × 2.2 × 10⁶ ms^-1
∆v = 0.22 × 10⁴ = 2.2 × 10³ ms^-1
∆x. ∆v.m = \(\frac{h}{4π}\)

∆x = 2.635 × 10^-8
Uncertainty in position = 2.635 × 10^-8

Question 27.
Distinguish between diffusion and effusion?
Answer:
Diffusion:

1. Diffusion is the spreading of molecules of a substance throughout a space or a second subsance.
2. Diffusion refers to the ability of the gases to mix with each other.
3. E.g; Spreading of something such as brown tea liquid spreading through the water in a tea cup.

Effusion:

1. Effusion is the escape of gas molecules through a very small hole in a membrane into an evacuated area.
2. Effusion is a ability of a gas to travel through a small pin-hole.
3. E.g; Pouring out something like the soap studs bubbling out from a bucket of water.

Question 28.
For a chemical reaction the values of ∆H and ∆S at 300 K are – 10 kJ mol^-1 and – 20 JK^-1 mol^-1 respectively. What is the value of ∆G of the reaction? Calculate the ∆G of a reaction at 600K assuming ∆H and ∆S values are constant. Predict the nature of the reaction?
Answer:
Given:
∆H = -10 kJ mol^-1 = -10000 J mol^-1
∆S = – 20 JK^-1 mol^-1
T = 300 K

∆G?
∆G = ∆H – T∆S
∆G = -10 kJ mol^-1 – 300 K × (-20 × 10^-3) kJ K^-1 mol^-1
∆G = (-10 + 6) kJ mol^-1
∆G = – 4 kJ mol^-1

At 600 K,
∆G = – 10 kJ mol^-1 – 600 K × (-20 × 10^-3) k^-1 mol^-1
∆G = (-10 + 12) kJ mol^-1
∆G + 2 kJ mol^-1
The value of ∆G is negative at 300K and the reaction is spontaneous, but at 600K the value ∆G becomes positive and the reaction is non-spontaneous.

Question 29.
For the reaction: A₂(g) + B₂(g) ⇄ 2AB(g); H is -∆ve.
The following molecular scenes represent different reaction mixture (A – light grey, B-dark grey)

1. Calculate the equilibrium constant K_p and K_c.
2. For the reaction mixture represented by scene (x), (y) the reaction proceed in which directions?
3. What is the effect of increase in pressure for the mixture at equilibrium?

Answer:

K_c > Q i.e; forward reaction is favoured.

(III) Since ∆n_g = 2 -2 = 0, thus, pressure has no effect. So by increasing the pressure, equilibrium will not be affected.

Question 30.
Derive the relationship between the relative lowering of vapour pressure and mole fraction of the solute?
Answer:

Question 31.
Differentiate between the principle of estimation of nitrogen in an organic compound by

1. Dumas method
2. Kjeldahl’s method

Answer:

1. Dumas method:
The organic compound is heated strongly with excess of CuO (Cupic Oxide) in an atmosphere of CO₂ where free nitrogen, CO₂ and H₂O are obtained.

2. Kjeldahl’s method:
A known mass of the organic compound is heated strongly with cone. H₂SO₄, a little amount of potassium sulphate arid a little amount of mercury (as catalyst). As a result of reaction, the nitrogen present in the organic compound is converted to ammonium sulphate.

Question 32.
In what way free radical affect the human body?
Answer:

1. Free radicals can disrupt cell membranes.
2. Increase the risk of many forms of cancer.
3. Damage the interior lining of blood vessels.
4. Eads to a high risk of heart disease and stroke.

Question 33.
Dissolved oxygen in water is responsible for aquatic life. What processes are responsible for the reduction in dissolved oxygen in water?
Answer:

1. Organic matter such as leaves, grass, trash can pollute water. Microorganisms present in water can decompose these organic matter and consume dissolved oxygen in water.
2. Eutrophication is a process by which water bodies receive excess nutrients that stimulates excessive plant growth.
3. This enhanced plant growth in water bodies is called algal bloom.
4. The growth of algae in extreme abundance covers the water surface and reduces the oxygen concentration in water. Thus, bloom-infeded water inhibits the growth of other living organisms in the water body.
5. This process in which the nutrient rich water support a dense plant population, kills animal life by depriving it of oxygen and results in loss of biodiversity is known as eutrophication.

PART – IV

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

Question 34 (a).
(I) Calculate the equivalent mass of sulphuric acid?
(II) The reaction between aluminium and ferric oxide can generate temperatures up to 3273 K and is used in welding metals.
(Atomic mass of Al = 27 u Atomic mass of O = 16 u)
2Al + Fe₂O₃ → Al₂O₃ + 2Fe; If, in this process, 324 g of aluminium is allowed to react with 1.12 kg of ferric oxide.
(a) Calculate the mass of Al₂O₃ formed.
(b) How much of the excess reagent is left at the end of the reaction?

[OR]

(b) (I) Consider the following electronic arrangements for the d⁵ configuration?

(a)

(b)

(c)

1. Which of these represents the ground state?
2. Which configuration has the maximum exchange energy?

(II) An ion with mass number 56 contains 3 units of positive charge and 30.4% more neutrons than electrons. Assign symbol to the ion?
Answer:
(a) (I) Equivalent mass of sulphuric acid:
Sulphuric acid = H₂SO₄
Molar mass of Sulphuric acid = 2 + 32 + 64 = 96
Basicity of Sulphuric acid = 2

= \(\frac{96}{2}\) = 49 g eq^-1

(II) (a)

As per balanced equation 54 g Al is required for 112 g of iron and 102 g of Al₂O₃.
54 g of Al gives 102 g of Al₂O₃.
∴ 324 g of Al will give \(\frac{102}{54}\) × 324 = 612 g of AlcO₃

(b) 54 g of Al requires 160 g of Fe₂O₃ for welding reaction.
∴ 324 g of Al will require \(\frac{160}{54}\) × 324 = 960 g of Fe\(\frac{102}{54}\)O₃
∴ Excess Fe₂O₃ -Unreacted Fe₂O₃ = 1120 – 960 = 160 g 160 g of exces reagent is left at the end of the reaction.

[0R]

(b)
(I) 1.
2.

(II) Let the no. of electrons in the ion = x
∴ The no. of the protons = x + 3 (as the ion has three units positive charge)
and the no. of neutrons = x + \(\frac{30.4x}{100}\) = x + 0.304 x
Now, mass number of ion = Number of protons + Number of neutrons
= (x + 3) + (x + 0.304 x)
∴ 56 = (x + 3) + (x + 0.304 x) or 2.304 x = 56 – 3 = 53
x = \(\frac{53}{2.304}\) = 23
Atomic number of the ion (or element) = 23 + 3 = 26
The element with atomic number 26 is iron (Fe) and the corresponding ion is Fe³⁺.

Question 35 (a).
(I) State the Newland’s law of octaves?
(II) What are the two exceptions of block division in the periodic table?

[OR]

(b) (I) Complete the following reactions.
(a)

(b) 2 BeCl₂ + LiaH₄ →?

(II) What happens when quick lime reacts with
(a) H₂O and
(b) CO₂?

(I) The Law of octaves states that, “when elements are arranged in the order of increasing atomic weights, the properties of the eighth element are a repetition of the properties of the first element”.

(II)

1. Helium has two electrons. Its electronic configuration is 1s². As per the configuration, it is supposed to be placed in ‘s’ block, but actually placed in 18th group which belongs to ‘p’ block. Because it has a completely filled valence shell as the other elements present in 18th group. It also resembles with 18th group elements in other properties. Hence helium is placed with other noble gases.

2. The other exception is hydrogen. It has only one s-electron and hence can be placed in group 1. It can also gain an electron to achieve a noble gas arrangement and hence it can behave as halogens (17^th group elements). Because of these assumptions, position of hydrogen becomes a special case. Finally, it is placed separately at the top of the periodic table.

[OR]

(b) (I) (a) Beryllium oxide is heated with carbon and chloride to get BeCl₂

(b) Beryllium chloride is treated with LiAlH₄ to get beryllium hydride.
2BeCl₂ + LiAlH₄ → 2BeH₂ + Licl + Alcl₃

(II) (a) CaO + H₂O → Ca(OH)₂ (calcium hydroxide)
(b) CaO + CO₂ → CaO₃ (calcium carbonate)

Question 36 (a).
(I) State the first law of thermodynamics?
(II) Calculate the enthalpy of combustion of ethylene at 300 Kc at constant pressure, if its heat of combustion at constant volume (∆U) is -1406 kJ?

[OR]

(b)
(I) Explain how the equilibrium constant Kc predict the extent of a reaction? (3)
(II) Explain about the effect of catalyst in an equilibrium reaction? (2)
Answer:
(a) (I) The first law of thermodynamics states that “the total energy of an isolated system . remains constant though it may change from one form to another” (or) Energy can neither be created nor destroyed, but may be converted from one form to another.
(II) The complete ethylene combustion reaction can be written as,

C₂H_4(g) + 3O_2(g) → 2CO_2(g) + 2H₂O_(l)
ΔU = -1406 kJ
Δn = n_p(g) – n_r(g)
Δn = 2 – 4 – 2
ΔH = ΔU + RTΔn_g
ΔH = -1406 + (8.314 × 10^-3 × 300 × (-2)) ΔH = -1410.9 kJ

[OR]

(b) (I)

1. The value of equilibrium constant K_C tells us the extent of the reaction i.e., it indicatehow far the reaction has proceeded towards product formation at a given temperature.
2. A large value of K_C indicates that the reaction reaches equilibrium with high product yield on the other hand, lower value of K_C indicates that the reaction reaches equilibrium with low product yield.
3. If K_C > 10³, the reaction proceeds nearly to completion.
4. If K_C < 10^-3 the reaction rarely proceeds.
5. It the K_C is in the range 10^-3 to 10³, significant amount of both reactants and products are present at equilibrium.

(II) Addition of catalyst does not affect the state of equilibrium. The catalyst increases the rate of both the forward and reverse reactions to the same extent. Hence it does not change the equilibrium composition of the reaction mixture.

Question 37 (a).
(I) Briefly explain geometrical isomerism in alkenes by considering 2- butene as an example.
2 – butene: Geometrical isomerism: CH₃ – CH = CH – CH₃ 

(II) What is meant by condensed structure? Explain with an example.

[OR]

(b)
(I) Why cut apple turns a brown colour?
(II) Predict the product for the following reaction,

1.

2.

3.

Answer:
(a) (I)

• Geometrical isomers are the stereoisomers which have different arrangement of groups or atoms around a rigid framework of double bonds. This type of isomerism occurs due to restricted rotation of double bonds or about single bonds in cyclic compounds.
• In 2-butene, the carbon-carbon double bond is sp² hybridised. The carbon-carbon double bond consists of a s bond and a p bond. The presence of p bond lock the molecule in one position. Hence, rotation around C = C bond is not possible.
• 
• These two compounds are termed as geometrical isomers and are termed as cis and transform.
• The cis isomer is the one in which two similar groups are on the same side of the double bond. The trans isomer is that in which two similar groups are on the opposite side of the double bond. Hence, this type of isomerism is called cis-trans isomerism.

(II) The bond line structure can be further abbreviated by omittiilg all the these dashes representing covalent bonds and by indicating the number of identical groups attached to an atom by a subscript. The resulting expression of the compound is called a condensed structural formula.
e.g., 1,3 – butadiene.

[OR]

(b) (I)

1. Apples contains an enzyme called polyphenol oxidase (PPO) also known as tyrosinase.
2. Cutting an apple exposes its cells to the atmospheric oxygen and oxidizes the phenolic compounds present in apples. This is called the “enzymatic browning” that turns a cut apple brown.
3. In addition to apples, enzymatic browning is also evident in bananas, pears, avocados and even potatoes.

Question 38 (a).
Suggest the route for the preparation of the following from benzene?

1. 3 – chloro-nitrobenzene
2. 4 – chlorotoluene
3. Bromobenzene
4. m – dinitrobenzene

[OR]

(b) A hydrocarbon C₃H₆ (A) reacts with HBr to form compound (B). Compound (B) reacts with aqueous potassium hydroxide to give (C) of molecular formula C₃H₆O. What are (A) (B) and (C). Explain the reactions?
Answer:
(a)
1. Preparation of 3 – chloronitro – benzene from benzene: Benzene undergoes nitration and followed by chlorination and it leads to the formation of 3 – chloronitrobenzene.

2. Preparation 4-chlorotoulene from benzene: Benzene undergoes Friedal craft’s alkylation followed by chlorination and it leads to the formation of 4 – chlorotoulene.

3. Preparation of Bromobenzene from benzene: Benzene undergo bromination to give bromobenzene.

4. Preparation of m-dinitrobenzene from benzene: Benzene undergo twice the time nitration to give m-dinitrobenzene.

[OR]

(b)
1. The hydrocarbon with molecular formula C₃H₆ (A) is identified as propene,
CH – CH = CH₂
2. Propene reacts with HBr to form bromopropane CH₃ – CH₂ – CH₂Br as (B).

3. 1 – bromopropane react with aqueous potassium hydroxide to give 1 – propanol CH₃ – CH₂ – CH₂OH as (C).
4. 2 – bromo propane reacts with aqueous KOH to give 2-propanol as (C)

Students can Download Tamil Nadu 11th Physics Model Question Paper 3 English Medium Pdf, Tamil Nadu 11th 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 11th Physics Model Question Paper 3 English Medium

General 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 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
5. Question numbers 16 to 24 in Part II are two-mark questions. These are to be answered in about one or two sentences.
6. Question numbers 25 to 33 in Part III are three-mark questions. These are to be answered in about three to five short sentences.
7. 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
Maximum Marks: 70

PART – I

Answer all the questions: [15 × 1 = 15]

Question 1.
A new unit of length is chosen such that the speed of light in vacuum is unity. The distance between the Sun and the Earth in terms of the new unit, if light takes 8 minute and 20 sec to cover the distance is …………………..
(a) 100 new unit
(b) 300 new unit
(c) 500 new unit
(d) 700 new unit
Hint:
Speed is unity = 1 unit/sec
Time = 8 min and 20 sec = 500 sec
Distance b/w sun and earth = Speed × Time
= 1 × 500 = 500 unit
Answer:
(c) 500 new unit

Question 2.
For a satellite moving in an orbit around the Earth, the ratio of kinetic energy to potential energy is ………………….
(a) 2
(b) 1 : 2
(c) 1 : \(\sqrt{2}\)
(d) \(\sqrt{2}\)
Hint:
\(\frac { GMm }{ R^{ 2 } } \) = mω²R
K.E = \(\frac{1}{2}\)Iω² = \(\frac{1}{2}\)mR²ω² = \(\frac{GMm}{2R}\)
P.E = – \(\frac{GMm}{R}\) ⇒ So \(\frac{K.E}{|P.E|}\) = \(\frac{1}{2}\)
Answer:
(b) 1 : 2

Question 3.
In the equilibrium position a body has ……………….
(a) Maximum potential energy
(b) Minimum potential energy
(c) Minimum kinetic energy
(d) Neither maximum nor minimum potential energy
Answer:
(c) Minimum kinetic energy

Question 4.
The centrifugal force appears to exist ………………….
(a) Only in inertial frames
(b) Only in rotating frames
(c) In any accelerated frame
(d) Both in inertial and non-inertial frames
Answer:
(b) Only in rotating frames

Question 5.
A particle is moving with a constant velocity along a line parallel to positive x-axis. The magnitude of its angular momentum with respect to the origin is …………………..
(a) Zero
(b) Increasing with x
(c) Decreasing with x
(d) Remaining constant
Answer:
(d) Remaining constant

Question 6.
When 8 droplets of water of radius 0.5 mm combine to form a single droplet. The radius of it is …………………
(a) 4 mm
(b) 2 mm
(c) 1 mm
(d) 8 mm
Hint:
Volume of 8 droplets of water = 8 × \(\frac{4}{3}\) π(0.5)³
When each droplet combine to form one volume remains conserved
R³ = 8 × (0.5)³
R³ = (8 × (0.5)³)
R³ = 2 × 0.5 = 1 mm
Answer:
(c) 1 mm

Question 7.
Pressure head in Bernoulli’s equation is …………………
(a) \(\frac { P_{ \rho } }{ g } \)
(b) \(\frac { P }{ \rho g } \)
(c) ρg
(d) Pρg
Answer:
(b) \(\frac { P }{ \rho g } \)

Question 8.
The angle between particle velocity and wave velocity in a transverse wave is ……………………
(a) Zero
(b) π/4
(c) π/2
(d) π
Answer:
(c) π/2

Question 9.
If the masses of the Earth and Sun suddenly double, the gravitational force between them will …………………….
(a) Remains the same
(b) Increase two times
(c) Increase four times
(d) Decrease two times
Answer:
(c) Increase four times

Question 10.
A mobile phone tower transmits a wave signal of frequency 900 MHz, the length of the transmitted from the mobile phone tower ……………………
(a) 0.33 m
(b) 300 m
(c) 2700 × 10⁸m
(d) 1200 m
Hint:
f = 900 MHz = 900 × 10⁶ Hz
Speed of wave (c) = 3 × 10⁶ ms^-1
λ = \(\frac{v}{f}\) = \(\frac { 3\times 10^{ 8 } }{ 900\times 10^{ 6 } } \) = \(\frac{1}{3}\) = 0.33m
Answer:
(a) 0.33 m

Question 11.
The displacement y of a wave travelling in the x direction is given by
y = (2 × 10^-3) sin (300 t – 2x + \(\frac { \pi }{ 4 } \)), where x and y are measured in metres and t in second. The speed of the wave is …………………
(a) 150 ms^-1
(b) 300 ms^-1
(c) 450 ms^-1
(d) 600 ms^-1
Hint:
From standard equation of wave, Y = a sin (ωt – kx + ϕ)
ω = 300 ; k = 2
Speed of wave, V = \(\frac{ω}{k}\) = \(\frac{300}{2}\) = 150ms^-1
Answer:
(a) 150 ms^-1

Question 12.
The increase in internal energy of a system is equal to the workdone on the system. The process does the system undergoes is ……………………
(a) Isochoric
(b) Adiabatic
(c) Isobaric
(d) Isothermal
Answer:
(d) Isothermal

Question 13.
The minimum velocity with which a body of mass m must enter a vertical loop of radius R so that it can complete the loop is ……………………..
(a) \(\sqrt{2gR}\)
(b) \(\sqrt{3gR}\)
(c) \(\sqrt{5gR}\)
(d) \(\sqrt{gR}\)
Answer:
(c) \(\sqrt{5gR}\)

Question 14.
If the rms velocity of the molecules of a gas in a container be doubled then the pressure of the gas will.
(a) Becomes 4 times of the previous value
(b) Becomes 2 times of its previous value
(c) Remains same
(d) Becomes \(\frac{1}{4}\) of its previous value
Hint:

Answer:
(a) Becomes 4 times of the previous value

Question 15.
Gravitational mass is proportional to gravitational ………………….
(a) Intensity
(b) Force
(c) Field
(d) All of these
Answer:
(b) Force

PART – II

Answer any six questions in which Q. No 23 is compulsory. [6 × 2 = 12]

Question 16.
Write any four postulates of Kinetic theory of gases?
Answer:

1. A gas consists of a very large number of molecules. Each one is a perfectly identical elastic sphere.
2. The molecules of a gas are in a state of continuous and random motion. They move in all directions with all possible velocities.
3. The size of each molecule is very small as compared to the distance between them. Hence, the volume occupied by the molecule is negligible in comparison to the volume of the gas:
4. There is no force of attraction or repulsion between the molecules and the walls of the container.

Question 17.
Draw the free body diagram of the book at rest on the table?
Answer:

Question 18.
Three block are connected as shown in fig on a horizontal frictionless table. If m₁ = 1 kg, m₂ = 8 kg, m₃ = 27 kg and T₃ = 36 N then calculate tension T₂?
Answer:

Acceleration acquired by all blocks a = \(\frac { T_{ 3 } }{ m_{ 1 }+m_{ 2 }+m_{ 3 } } \) = \(\frac{36}{36}\) = 1ms^-2
∴ Tension T₂ = (m₁ + m₂) a
= (1 + 8) × 1 = 9N

Question 19.
What is power? Give its dimensional formula?
Answer:
The rate of work done is called power. Dimensional formula of power is ML² T^-3

Question 20.
What are geostationary and polar satellites?
Answer:
Geostationary Satellite: It is the satellite which appears at a fixed position and at a definite height to an observer on Earth.
Polar Satellite: It is the satellite which revolves in polar orbit around the Earth.

Question 21.
An iceberg of density 900 kg m^-3 is floating in water of density 1000 kg m^-3. What is the percentage of volume of iceberg outside the water?
Answer:
Fraction of volume inside water = Relative density of the body
\(\frac { V’ }{ V } \) = \(\frac { \rho }{ \rho ‘ } \) = \(\frac{900}{1000}\) = 0.9
Fraction of volume outside water = 1 – 0.9 = 0.1
Percentage of volume outside water = 0.1 × 100 = 10%

Question 22.
State stoke’s law and define terminal velocity?
Answer:
Stoke’s law:
When a body falls through a highly viscous liquid, it drags the layer of the liquid immediately in contact with it. This results in a relative motion between the different layers of the liquid. As a result of this, the falling body experiences a viscous force F.

Stoke performed many experiments on the motion of small spherical bodies in different fluids and concluded that the viscous force F acting on the spherical body depends on

1. Coefficient of viscosity q of the liquid
2. Radius a of the sphere and
3. Velocity v of the spherical body

Dimensionally it can be proved that ∴ F = k ηav
Experimentally Stoke found that k = 6π
This is Stoke’s law

Terminal velocity:
Terminal velocity of a body is defined as the constant velocity acquired by a body while falling through a viscous liquid.

Question 23.
The Earth without its atmosphere would be hospitably cold. Explain why?
Answer:
The lower layers of Earth’s atmosphere reflect infrared radiations from Earth back to the surface of Earth. Thus the heat radiation received by the earth from the Sun during the day are kept trapped by the atmosphere. If atmosphere of Earth were not there, its surface would become too cold to live.

Question 24.
A body A is projected upwards with velocity v₁ Another body B of same mass is proj eeted at an angle of 45°. Both reach the same height. Calculate the ratio of their initial kinetic energies?
Answer:
As A and B attain the same height therefore vertical component of initial velocity of B is equal to initial velocity of A
v₂ cos 45° = V₁ (or) \(\frac { v_{ 2 } }{ \sqrt { 2 } } \) = v₁

PART – III

Answer any six questions in which Q.No. 29 is compulsory. [6 × 3 = 18]

Question 25.
Explain the rules for counting significant figures with examples?
Rules for counting significant figures:
Answer:

Question 26.
Elastic headon collision, consider two particles one is moving and another one is stationary with their respective masses m and \(\frac { M }{ m } \). A moving particle meets collides elastically on stationary particle in the opposite direction. Find the kinetic energy of the stationary particle after a collision?
Answer:
mass of the moving particle m₁ = m (say)
mass of the stationary particle m₁ = \(\frac { 1 }{ m } \) M
Velocity of the moving particle before collision = v_1i (say)
Velocity of the stationary particle before collision = v_2i = 0
Velocity of the stationary particle after collision = v_2f (say)

Kinetic energy of the stationary particle after a collision

Question 27.
Calculate the angle for which a cyclist bends when he turns a circular path of length 34.3 m in \(\sqrt{22}\) s?
Answer:
Given Data:
l = 34.3 m, t = \(\sqrt{22}\) , g = 9.8 ms^-2, θ = ?
If r is radius of circular path, then length of path = 2πr = 34.3 m
r = \(\frac { 33.4 }{ 2\pi } \) and time taken t = \(\sqrt{22}\)s

As tan θ = \(\frac { v^{ 2 } }{ rg } \)
∴ tan θ = (\(\frac { 34.3 }{ \sqrt { 22 } } \))² × \(\frac { 2\pi }{ 34.3\times 9.8 } \)
tan θ = \(\frac { 34.3\times 34.3 }{ 22 } \) × \(\frac{2×22}{7×343×9.8}\) = \(\frac{34.3×2}{68.6}\) = 1 [∴θ = 45°]

Question 28.
Explain how density, moisture affect the velocity of sound in gases?
Answer:
Effect of density:
Let us consider two gases with different densities having same temperature and pressure. Then the speed of sound in the two gases are

Taking ratio of equation (1) and equation (2) we get

For gases having same value of γ,
\(\frac { v_{ 1 } }{ v_{ 2 } } \) = \(\sqrt { \frac { \rho _{ 2 } }{ \rho _{ 1 } } } \)
Thus the velocity of sound in a gas is inversely proportional to the square root of the density of the gas.

Effect of moisture (humidity):
We know that density of moist air is 0.625 of that of dry air, which means the presence of moisture in air (increase in humidity) decreases its density. Therefore, speed of sound increases with rise in humidity. From equation:
v = \(\sqrt { \frac { \gamma \rho }{ \rho } } \)

Let ρ₁, v₁ = and ρ₂, v₂ be the density and speeds of sound in dry air and moist air, respectively.

Since P is the atmospheric pressure, it can be shown that
\(\frac { \rho _{ 2 } }{ \rho _{ 1 } } \) = \(\frac { P }{ p_{ 1 }+0.625p_{ 2 } } \)
where p₁ and p₂ are the partial pressures of dry air and water vapour respectively. Then

Question 29.
Explain
(a) Why there are no lunar eclipse and solar eclipse every month?
(b) Why do we have seasons on earth?
Answer:
(a) If the orbits of the Moon and Earth lie on the same plane, during full Moon of every month, we can observe lunar eclipse. If this is so during new Moon we can observe solar eclipse.

But Moon’s orbit is tilted 5° with respect to Earth’s orbit. Due to this 5° tilt, only during certain periods of the year, the Sun, Earth and Moon align in straight line leading to either lunar eclipse or solar eclipse depending on the alignment.

(b) The common misconception is that ‘Earth revolves around the Sun, so when the Earth is very far away, it is winter and when the Earth is nearer, it is summer’.

Actually, the seasons in the Earth arise due to the rotation of Earth around the Sun with 23.5° tilt. Due to this 23.5° tilt, when the northern part of Earth is farther to the Sun, the southern part is nearer to the Sun. So when it is summer in the northern hemisphere, the southern hemisphere experience winter.

Question 30.
When a person breathes, his lungs can hold up to 5.5 1 of air at body temperature 37°C and atmospheric pressure (1 atm = 101 kPa). This air contains 21% oxygen, calculate the number of oxygen molecules in the lungs?
Answer:
We can treat the air inside the lungs as an ideal gas. To find the number of molecules, we can use the ideal gas law.
PV = NkT
Here volume is given in the Litre. 1 Litre is volume occupied by a cube of side 10 cm
1 Litre = 10 cm × 10 cm × 10 cm = 10^-3m^-3
N = \(\frac{PV}{kT}\) = \(\frac { 1.01\times 10^{ 5 }\times 5.5\times 10^{ -3 } }{ 1.38\times 10^{ -23 }\times 310 } \)
= 1.29 × 10²³ × \(\frac{21}{100}\)
Number of oxygen molecules = 2.7 × 10²² molecules

Question 31.
Give any five properties of vector product of two vectors?
Answer:
(I) The vector product of any two vectors is always another vector whose direction is perpendicular to the plane containing these two vectors, i.e., orthogonal to both the vectors \(\vec { A } \) and \(\vec { B } \), even though the vectors AandB may or may not be mutually orthogonal.

(II) The vector product of two vectors is not commutative, i.e., \(\vec { A } \) × \(\vec { B } \) ≠ \(\vec { B } \) × \(\vec { A } \) . But, \(\vec { A } \) × \(\vec { B } \) = –\(\vec { B } \) × \(\vec { A } \).

Here it is worthwhile to note that |\(\vec { A } \) × \(\vec { B } \)| = |\(\vec { B } \) × \(\vec { A } \)| = AB sin θ i.e., in the case of the product vectors \(\vec { A } \) × \(\vec { B } \) and \(\vec { B } \) × \(\vec { A } \), the magnitudes are equal but directions are opposite to each other.

(III) The vector product of two vectors will have maximum magnitude when sin 0 = 1, i.e., θ = 90° i.e., when the vectors \(\vec { A } \) and \(\vec { B } \) are orthogonal to each other.
(\(\vec { A } \) × \(\vec { B } \))_max = AB\(\hat { n } \)

(IV) The vector product of two non-zero vectors will be minimum when sin 0 = 0, i.e., 0 = 0° or 180°
(\(\vec { A } \) × \(\vec { B } \))_max = 0
i.e., the vector product of two non-zero vectors vanishes, if the vectors are either parallel or antiparallel.

(V) The self-cross product, i.e., product of a vector with itself is the null vector
\(\vec { A } \) × \(\vec { A } \) = AA sin 0°\(\hat { n } \) = \(\vec { 0 } \)
In physics the null vector \(\vec { 0 } \) is simply denoted as zero.

Question 32.
Why does a porter bend forward w hile carrying a sack of rice on his back?
Answer:
When a porter carries a sack of rice, the line of action of his centre of gravity will go away from the body. It affects the balance, to avoid this he bends. By which centre of gravity will realign within the body again. So balance is maintained.

Question 33.
A piece of wood of mass m is floating erect in a liquid whose density is p. If it is slightly pressed down and released, then executes simple harmonic motion. Show that its time period of oscillation is T = 2π\(\sqrt{m/Agρ}\)
Answer:
Spring factor of liquid(k) = Aρg
Inertia factor of wood = m
Time period T = 2π = image 12
T = 2π\(\sqrt{m/Aρg}\)

PART – IV

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

Question 34 (a).
Describe the vertical oscillations of a spring?
Answer:
Vertical oscillations of a spring: Let us consider a massless spring with stiffness constant or force constant k attached to a ceiling as shown in figure. Let the length of the spring before loading mass m be L.

If the block of mass m is attached to the other end of spring, then the spring elongates by a length. Let F, be the restoring force due to stretching of spring. Due to mass m, the gravitational force acts vertically downward. We can draw free-body diagram for this system as shown in figure. When the system is under equilibrium,

F₁ + mg = 0 ……………… (1)
But the spring elongates by small displacement 1, therefore,
F₁ ∝ l ⇒ F₁ = -kl ……………….. (2)
Substituting equation (2) in equation (1) we get
-kl + mg = 0
mg = kl or
\(\frac{m}{k}\) = \(\frac{l}{g}\) ………………….. (3)

Suppose we apply a very small external force on the mass such that the mass further displaces downward by a displacement y, then it will oscillate up and down. Now, the restoring force due to this stretching of spring (total extension of spring is y + 1) is
F₂ ∝ (y + l)
F₂ = -k(y + l) = -ky – kl …………………… (4)

Since, the mass moves up and down with acceleration \(\frac{d^{2} y}{d t^{2}}\), by drawing the free body diagram for this case we get
-ky – kl + mg = m \(\frac{d^{2} y}{d t^{2}}\) ……………………. (5)
The net force acting on the mass due to this stretching is
F = F₂ + mg
F = -ky – kl + mg …………………… (6)
The gravitational force opposes the restoring force. Substituting equation (3) in equation (6), we get
F = – ky- kl + kl = -ky
Applying Newton’s law we get
m \(\frac{d^{2} y}{d t^{2}}\) = -ky
\(\frac{d^{2} y}{d t^{2}}\) = –\(\frac{k}{m}\)y ………………… (7)
The above equation is in the form of simple harmonic differential equation. Therefore, we get the time period as
T = 2π\(\sqrt{m/k}\) second ……………………. (8)
The time period can be rewritten using equation (3)
T = 2π\(\sqrt{m/k}\) = 2πl\(\frac{1}{g}\) second ……………………. (9)
The accleration due to gravity g can be computed by the formula
g = 4π²\((\frac { 1 }{ T } )^{ 2 }\)ms^-2 …………………….. (10)

[OR]

(b) Derive poiseuille’s formula for the volume of a liquid flowing per second through a pipe under streamlined flow?
Answer:
Consider a liquid flowing steadily through a horizontal capillary tube. Let v = (\(\frac{1}{g}\)) be the volume of the liquid flowing out per second through a capillary tube. It depends on (1) coefficient of viscosity (η) of the liquid, (2) radius of the tube (r), and (3) the pressure gradient (\(\frac{P}{l}\)) . Then,
v ∝η^ar^b(\(\frac{P}{l}\))^c
v = kη^ar^b(\(\frac{P}{l}\))^c …………………….. (1)

where, k is a dimensionless constant.
Therefore, [v] = \(\frac { Volume }{ Time } \) = [L³T^-1]; [ \(\frac{dP}{dX}\) ] = \(\frac { Pressure }{ Distance } \) = [ML^-2T^-2]
[η] = [Ml^-1T^-1] and [r] = [L]

Substituting in equation (1)
[L³T^-1] = [ML^-1T^-1]^a[L]^b [ML^-2T^-2]^c
M⁰L³T^-1 = M^a+bL^-a+b-2cT^-a-2c = -1

So, equating the powers of M, L and T on both sides, we get
a + c = 0, – a + b – 2c = 3, and – a – 2c = – 1

We have three unknowns a, b and c. We have three equations, on solving, we get
a = – 1, b = 4 and c = 1

Therefore, equation (1) becomes,
v = kη^-1r⁴(\(\frac{P}{l}\))¹

Experimentally, the value of k is shown to be , we have \(\frac{π}{8}\), we have
v = \(\frac{\pi r^{4} \mathrm{P}}{8 \eta /}\)

The above equation is known as Poiseuille’s equation for the flow of liquid through a narrow tube or a capillary tube. This relation holds good for the fluids whose velocities are lesser than the critical velocity (v_c).

Question 35 (a).
Describe briefly simple harmonic oscillation as a projection of uniform circular motion?
Answer:
Consider a particle of mass m moving with unifonn speed v along the circumference of a circle whose radius is r in anti-clockwise direction (as shown in figure). Let us assume that the origin of the coordinate system coincides with the center O of the circle.

If ω is the angular velocity of the particle and θ the angular displacement of the particle at any instant of time t, then θ = ωt. By projecting the uniform circular motion on its diameter gives a simple harmonic motion.

This means that we can associate a map (or a relationship) between uniform circular (or revolution) motion to vibratory motion. Conversely, any vibratory motion or revolution can be mapped to unifonn circular motion. In other words, these two motions are similar in nature.

Let us first project the position of a particle moving on a circle, on to its vertical diameter or on to a line parallel to vertical diameter as shown in figure. Similarly, we can do it for horizontal axis or a line parallel to horizontal axis.

The projection of uniform circular motion on a diameter of SHM:
As a specific example, consider a spring mass system (or oscillation of pendulum). When the spring moves up and down (or pendulum moves to and fro), the motion of the mass or bob is mapped to points on the circular motion.

Thus, if a particle undergoes uniform circular motion then the projection of the particle on the diameter of the circle (or on a line parallel to the diameter) traces straight line motion which is simple harmonic in nature. The circle is known as reference circle of the simple harmonic motion. The simple harmonic motion can also be defined as the motion of the projection of a particle on any diameter of a circle of reference.

[OR]

(b) State and prove Bernoulli’s theorem for a flow of incompressible non viscous and stream lined flow of fluid?
Answer:
Bernoulli’s theorem:
According to Bernoulli’s theorem, the sum of pressure energy, kinetic energy, and potential energy per unit mass of an incompressible, non-viscous fluid in a streamlined flow remains a constant. Mathematically,
\(\frac{P}{ρ}\) + \(\frac{1}{2}\)v² + gh – constant
This is known as Bernoulli’s equation.
Proof:
Let us consider a flow of liquid through a pipe AB. Let V be the volume of the liquid when it enters A in a time t. Which is equal to the volume of the liquid leaving B in the same time. Let a_A, v_A and P_A be the area of cross section of the tube, velocity of the liquid and pressure exerted by the liquid at A respectively.

Let the force exerted by the liquid at A is
F_A = P_Aa_A

Distance travelled by the liquid in time t is d = v_At
Therefore, the work done is W = F_Ad = P_Aa_Av_At
But a_Av_At = a_Ad = V, volume of the liquid entering at A.

Thus, the work done is the pressure energy (at A), W = F_Ad = P_AV

Pressure energy per unit volume at
A = \($\frac{\text { Pressure energy }}{\text { Volume }}$\) = \(\frac { P_{ A }V }{ V } \) = P_A

Pressure energy per unit mass at
A = \($\frac{\text { Pressure energy }}{\text { Mass }}$\) = \(\frac { P_{ A }V }{ m } \) = \(\frac { P_{ A } }{ \frac { m }{ V } } \) = \(\frac { P_{ A } }{ \rho } \)

Since m is the mass of the liquid entering at A in a given time, therefore, pressure energy of the liquid at A is
EP_A = P_AV = P_AV × (\(\frac{m}{m}\)) = m\(\frac { P_{ A } }{ \rho } \)

Potential energy of the liquid at A,
PE_A = mgh_A

Due to the flow of liquid, the kinetic energy of the liquid at A,
KE_A = \(\frac{1}{2}\)mv^2_A

Therefore, the total energy due to the flow of liquid at A,
E_A = EP_A + KE_A + PE_A
E_A = \(m \frac{P_{A}}{\rho}+\frac{1}{2} m v_{A}^{2}+m g h_{A}\)

Similarly, let a_B, V_B and P_B be the area of cross section of the tube, velocity of the liquid and pressure exerted by the liquid at B. Calculating the total energy at F_B, we get .
\(\mathrm{E}_{\mathrm{B}}=m \frac{\mathrm{P}_{\mathrm{B}}}{\rho}+\frac{1}{2} m v_{\mathrm{B}}^{2}+m g h_{\mathrm{B}}\)
From the law of conservation of energy.
E_A = E_B

Thus, the above equation can be written as
\(\frac { P }{ \rho g } \) + \(\frac{1}{2}\) \(\frac { v^{ 2 } }{ g } \) + h = Constant

The above equation is the consequence of the conservation of energy which is true until there is no loss of energy due to friction. But in practice, some energy is lost due to friction. This arises due to the fact that in a fluid flow, the layers flowing with different velocities exert frictional forces on each other. This loss of energy is generally converted into heat energy. Therefore, Bernoulli’s relation is strictly valid for fluids with zero viscosity or non-viscous liquids. Notice that when the liquid flows through a horizontal pipe, then
h = 0 ⇒ \(\frac { P }{ \rho g } \) + \(\frac{1}{2}\) \(\frac { v^{ 2 } }{ g } \) = Constant

Question 36 (a).
Explain perfect inelastic collision and derive an expression for loss of kinetic energy in perfect inelastic collision?
Answer:
In a perfectly inelastic or completely inelastic collision, the objects stick together permanently after collision such that they move with common velocity. Let the two bodies with masses m₁ and m₂ move with initial velocities u₁ and u₂ respectively before collision. Aft er perfect inelastic collision both the objects move together with a common velocity v as shown in figure.
Since, the linear momentum is conserved during collisions,

m₁u₁ + m₂u₂ = (m₁ + m₂) v

The common velocity can be computed by
v = \(\frac{m_{1} u_{1}+m_{2} u_{2}}{\left(m_{1}+m_{2}\right)}\) ………………….. (1)

Loss of kinetic energy in perfect inelastic collision;
In perfectly inelastic collision, the loss in kinetic energy during collision is transformed to another form of energy like sound, thermal, heat, light etc. Let KE_i be the total kinetic energy before collision and KE_f be the total kinetic energy after collision.
Total kinetic energy before collision,
KE_e = \(\frac{1}{2} m_{1} u_{1}^{2}+\frac{1}{2} m_{2} u_{2}^{2}\) …………………… (2)
Total kinetic energy after collision,
KE_f = \(\frac{1}{2}\left(m_{1}+m_{2}\right) v^{2}\) …………………….. (3)
Then the loss of kinetic energy is Loss of KE, ∆Q = KE_f – KE_i
= \(\frac{1}{2}\left(m_{1}+m_{2}\right) v^{2}-\frac{1}{2} m_{1} u_{1}^{2}-\frac{1}{2} m_{2} u_{2}^{2}\) ………………….. (4)
Substituting equation (1) in equation (4), and on simplifying (expand v by using the algebra (a + b)² = a² + b² + 2ab), we get
Loss of KE, ∆Q = \(\frac{1}{2}\) \(\left(\frac{m_{1} m_{2}}{m_{1}+m_{2}}\right)\) (u₁ – u₂)²

[OR]

(b) Derive an expression for maximum height attained, time of flight, horizontal range for a projectile in oblique projection?
Answer:

Maximum height (h_max):
The maximum vertical distance travelled by the projectile during the journey is called maximum height. This is determined as follows:
For the vertical part of the motion
\(v_{y}^{2}=u_{y}^{2}+2 a_{y} s\)
Here, u_y= u sin θ, a = -g, s = h_max, and at the maximum height v = 0

Time of flight (T_f):
The total time taken by the projectile from the point of projection till it hits the horizontal plane is called time of flight. This time of flight is the time taken by the projectile to go from point O to B via point A as shown in figure.
We know that s_y = u_yt + \(\frac{1}{2}\)a_yt²
Here, s_y = y = 0 (net displacement in y-direction is zero), u_y = u sin θ, a_y = -g, t = T_f, Then
0 = u sin θ T_f – \(\frac{1}{2} g \mathrm{T}_{f}^{2}\)
T_f = 2u \(\frac{sin θ}{g}\) …………………….. (2)

Horizontal range (R):
The maximum horizontal distance between the point of projection and the point on the horizontal plane where the projectile hits the ground is called horizontal range (R). This is found easily since the horizontal component of initial velocity remains the same. We can write.

Range R = Horizontal component of velocity % time of flight = u cos θ × T_f = \(\frac{u^{2} \sin 2 \theta}{g}\)
The horizontal range directly depends on the initial speed (u) and the sine of angle of projection (θ). It inversely depends on acceleration due to gravity ‘g’.

For a given initial speed u, the maximum possible range is reached when sin 2θ is
maximum, sin 2θ = 1. This implies 2θ = π/2 or θ = π/4
This means that if the particle is projected at 45 degrees with respect to horizontal, it attains maximum range, given by
R_max = \(\frac { u^{ 2 } }{ g } \).

Question 37 (a).
Explain the work-energy theorem in detail and also give three examples?
Answer:

1. If the work done by the force on the body is positive then its kinetic energy increases.
2. If the work done by the force on the body is negative then its kinetic energy decreases.
3. If there is no work done by the force on the body then there is no change in its kinetic energy, which means that the body has moved at constant speed provided its mass remains constant.
4. When a particle moves with constant speed in a circle, there is no change in the kinetic energy of the particle. So according to work energy principle, the work done by centripetal force is zero.

[OR]

(b) (i) Define molar specific heat capacity?
Answer:
Molar specific heat capacity is defined as heat energy required to increase the temperature of one mole of substance by IK or 1°C

(ii) Derive Mayer’s relation for an ideal gas?

Mayer’s relation: Consider p mole of an ideal gas in a container with volume V, pressure P and temperature T.

When the gas is heated at constant volume the temperature increases by dT. As no work is done by the gas, the heat that flows into the system will increase only the internal energy. Let the change in internal energy be dU.

If C_V is the molar specific heat capacity at constant volume, from equation.
C_V = \(\frac { 1 }{ \mu } \) \(\frac{dU}{dT}\) …………………… (1)
dU = µC_V dT ………………… (2)

Suppose the gas is heated at constant pressure so that the temperature increases by dT. If ‘Q’ is the heat supplied in this process and ‘dV’ the change in volume of the gas.
Q = pCpdT ……………. (3)

If W is the workdone by the gas in this process, then
W = P dV ………………….. (4)

But from the first law of thermodynamics,
Q = dU + W ………………… (5)

Substituting equations (2), (3) and (4) in (5), we get,
For mole of ideal gas, the equation of state is given by
\(\mu \mathrm{C}_{\mathrm{p}} d \mathrm{T}=\mu \mathrm{C}_{\mathrm{v}} d \mathrm{T}+\mathrm{P} d \mathrm{V}\)

Since the pressure is constant, dP = 0
C_pdT = C_VdT + PdV
∴ C_p = C_V + R (or) C_p – C_V = R …………………… (6)
This relation is called Mayer’s relation It implies that the molar specific heat capacity of an ideal gas at constant pressure is greater than molar specific heat capacity at constant volume.
The relation shows that specific heat at constant pressure (s_p) is always greater than specific heat at constant volume (s_v).

Question 38 (a).
Derive an expression of pressure exerted by the gas on the walls of the container?
Answer:
Expression for pressure exerted by a gas : Consider a monoatomic gas of N molecules each having a mass m inside a cubical container of side l.
The molecules of the gas are in random motion. They collide with each other and also with the walls of the container. As the collisions are elastic in nature, there is no loss of energy, but a change in momentum occurs.

The molecules of the gas exert pressure on the walls of the container due to collision on it. During each collision, the molecules impart certain momentum to the wall. Due to transfer of momentum, the walls experience a continuous force. The force experienced per unit area of the walls of the container determines the pressure exerted by the gas. It is essential to determine the total momentum transferred by the molecules in a short interval of time.

A molecule of mass m moving with a velocity \(\vec { v } \) having components (v_x, v_y, v_z) hits the right side wall. Since we have assumed that the collision is elastic, the particle rebounds with same speed and its x-component is reversed. This is shown in the figure. The components of velocity of the molecule after collision are (-v_x, v_y, v_z).

The x-component of momentum of the molecule before collision = mv_x
The x-component of momentum of the molecule after collision = – mv_x
The change in momentum of the molecule in x direction
= Final momentum – initial momentum = – mv_x – mv_x = – 2mv_x
According to law of conservation of linear momentum, the change in momentum of the wall = 2 mv_x
The number of molecules hitting the right side wall in a small interval of time ∆t.

The molecules within the distance of v_x∆t from the right side wall and moving towards the right will hit the wall in the time interval ∆t. The number of molecules that will hit the right side wall in a time interval ∆t is equal to the product of volume (Av_x∆t) and number density of the molecules (n).

Here A is area of the wall and n is number of molecules per \(\frac{N}{V}\) unit volume. We have assumed that the number density is the same throughout the cube.

Not all the n molecules will move to the right, therefore on an average only half of the n molecules move to the right and the other half moves towards left side.

The number of molecules that hit the right side wall in a time interval ∆t
= \(\frac{n}{2}\) Av_x∆t
In the same interval of time ∆t, the total momentum transferred by the molecules
\(\Delta \mathrm{P}=\frac{n}{2} \mathrm{A} v_{x} \Delta t \times 2 m v_{x}=\mathrm{A} v_{x}^{2} m n \Delta t\) ………………….. (2)
From Newton’s second law, the change in momentum in a small interval of time gives rise to force.

The force exerted by the molecules on the wall (in magnitude)
F = \(\frac{∆p}{∆t}\) = nmAv^2_x ……………………. (3)

Pressure, P = force divided by the area of the wall
P = \(\frac{F}{A}\) = nmAv^2_x ……………………….. (4)
p = \(nm\bar{v}_{x}^{2}\)

Since all the molecules are moving completely in random manner, they do not have same . speed. So we can replace the term vnmAv^2_x by the average \(\bar { v } \)^2_x in equation (4).
P = nm\(\bar { v } \)^2_x ……………………. (5)

Since the gas is assumed to move in random direction, it has no preferred direction of motion (the effect of gravity on the molecules is neglected). It implies that the molecule has same average speed in all the three direction. So, \(\bar{v}_{x}^{2}\) = \(\bar{v}_{y}^{2}\) = \(\bar{v}_{z}^{2}\). The mean square speed is written as
\(\bar{v}^{2}\) = \(\bar{v}_{x}^{2}\) + \(\bar{v}_{y}^{2}\) + \(\bar{v}_{z}^{2}\) = 3\(\bar{v}_{x}^{2}\)
\(\bar{v}_{x}^{2}\) = \(\frac{1}{3}\) \(\bar{v}^{2}\)
Using this in equation (5), we get
P = \(\frac{1}{3} n m \bar{v}^{2} \quad \text { or } P=\frac{1}{3} \frac{N}{V} m \bar{v}^{2}\) ………………….. (6)

[OR]

(b) Discuss the simple pendulum in detail?
Answer:
Simple pendulum

A pendulum is a mechanical system which exhibits periodic motion. It has a bob with mass m suspended by a long string (assumed to be massless and inextensible string) and the other end is fixed on a stand. At equilibrium, the pendulum does not oscillate and hangs vertically downward.

Such a position is known as mean position or equilibrium position. When a pendulum is displaced through a small displacement from its equilibrium position and released, the bob of the pendulum executes to and fro motion. Let l be the length of the pendulum which is taken as the distance between the point of suspension and the centre of gravity of the bob. Two forces act on the bob of the pendulum at any displaced position.

• The gravitational force acting on the body (\(\vec { F} \) = m\(\vec { g } \)) which acts vertically downwards.
• The tension in the string T which acts along the string to the point of suspension.

Resolving the gravitational force into its components:

1. Normal component: The component along the string but in opposition to the direction of tension, F_as = mg cos θ.
2. Tangential component: The component perpendicular to the string i.e., along tangential direction of arc of swing, F_ps = mg sin θ.

Therefore, The normal component of the force is, along the string,
\(\mathrm{T}-\mathrm{W}_{a s}=m \frac{v^{2}}{l}\)

Here v is speed of bob
T -mg cos θ = m \(\frac{v^{2}}{l}\)

From the figure, we can observe that the tangential component W_ps of the gravitational force always points towards the equilibrium position i.e., the direction in which it always points opposite to the direction of displacement of the bob from the mean position. Hence, in this case, the tangential force is nothing but the restoring force. Applying Newton’s second law along tangential direction, we have
\(m \frac{d^{2} s}{d t^{2}}+\mathrm{F}_{p s}=0 \Rightarrow m \frac{d^{2} s}{d t^{2}}=-\mathrm{F}_{p s}\)
\(m \frac{d^{2} s}{d t^{2}}=-m g \sin \theta\) …………………. (1)

where, s is the position of bob which is measured along the arc. Expressing arc length in terms of angular displacement i.e.,
s = lθ ………………… (2)
then its acceleration, \(\frac{d^{2} s}{d t^{2}}=l \frac{d^{2} \theta}{d t^{2}}\) …………………. (3)

Substituting equation (3) in equation (1), we get
\(\begin{aligned}
l \frac{d^{2} \theta}{d t^{2}} &=-g \sin \theta \\
\frac{d^{2} \theta}{d t^{2}} &=-\frac{g}{l} \sin \theta
\end{aligned}\) ………………….. (4)

Because of the presence of sin θ in the above differential equation, it is a non-linear differential equation (Here, homogeneous second order). Assume “the small oscillation approximation”, sin θ ~ 0, the above differential equation becomes linear differential equation.
\(\frac{d^{2} \theta}{d t^{2}}=-\frac{g}{l} \theta\) …………………… (5)

This is the well known oscillatory differential equation. Therefore, the angular frequency of this oscillator (natural frequency of this system) is
ω² = \(\frac{g}{l}\) …………………… (6)
∴ ω = \(\sqrt{g/l}\) in rad s^-1 ……………….. (7)

The frequency of oscillation is
f = \(f=\frac{1}{2 \pi} \sqrt{\frac{g}{l}} \text { in } \mathrm{Hz}\) ………………… (8)
and time period of sscillations is
T = 2π\(\sqrt{l/g}\) in second. ……………….. (9)

Students can download Maths Chapter 7 Mensuration Ex 7.2 Questions and Answers, Notes, Samacheer Kalvi 10th Maths Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Maths Solutions Chapter 7 Mensuration Ex 7.2

Question 1.
A 14 m deep well with inner diameter 10 m is dug and the earth taken out is evenly spread all around the well to form an embankment of width 5 m. Find the height of the embankment.

Answer:
Radius of the well (r₁) = 5 m
Depth of the well (h) = 14 m
Width of the embankment = 5 m
Outer radius (R) = 5 + 5 = 10 m
Let the height of the embankment be “H”
Volume of Earth in the embankment = Volume of the well
πH(R² – r²) = \(\pi r_{1}^{2} h\)
H(10² – 5²) = 5 × 5 × 14
H (100 – 25) = 5 × 5 × 14
H = \(\frac{5 \times 5 \times 14}{75}\) = 4.67 m
Height of the embankment = 4.67 m

Question 2.
A cylindrical glass with diameter 20 cm has water to a height of 9 cm. A small cylindrical metal of radius 5 cm and height 4 cm is immersed it completely. Calculate the rise of the water in the glass?
Answer:
Radius of the cylindrical glass (r) = 10 cm
Height of the water (h) = 9 cm
Radius of the cylindrical metal (R) = 5 cm
Height of the metal (H) = 4 cm
Let the height of the water raised be “h”
Volume of the water raised in the cylinder = Volume of the cylindrical metal
πr²h = πr²H
10 × 10 × h = 5 × 5 × 4
h = \(\frac{5 \times 5 \times 4}{10 \times 10}\) = 1 cm
Raise of water in the glass = 1 cm

Question 3.
If the circumference of a conical wooden piece is 484 cm then find its volume when its height is 105 cm.
Answer:
Circumference of the wooden piece = 484 cm
2πr = 484
2 × \(\frac{22}{7}\) × r = 484 cm
r = \(\frac{484 \times 7}{2 \times 22}\)
r = 77 cm
Height of the wooden piece (h) = 105 cm
Volume of the conical wooden piece = \(\frac{1}{3} \pi r^{2} h\) cu.units
= \(\frac{1}{3} \times \frac{22}{7} \times 77 \times 77 \times 105 \mathrm{cm}^{3}\)
= 22 × 11 × 77 × 35 cm³
= 652190 cm³
Volume of the wooden piece = 652190 cm³

Question 4.
A conical container is fully filled with petrol. The radius is 10m and the height is 15 m. If the container can release the petrol through its bottom at the rate of 25 cu. meter per minute, in how many minutes the container will be emptied. Round off your answer to the nearest minute.
Answer:
The radius of the conical container (r) = 10 m
Height of the container (h) = 15 m

Question 5.
A right-angled triangle whose sides are 6 cm, 8 cm and 10 cm is revolved about the sides containing the right angle in two ways. Find the difference in volumes of the two solids so formed.

Answer:
Three sides of a triangle are 6 cm, 8 cm and 10 cm.
Case (i): If the triangle is revolved about the side 6 cm, the cone will be formed with radius 6 cm and height 8 cm.
Volume of the cone = \(\frac{1}{3} \pi r^{2} h\) cu. units
= \(\frac{1}{3}\) × π × 6 × 6 × 8 = 96π cm³
Case (ii): If the triangle is revolved about the side 8 cm, the cone will be formed with radius 8 cm and height 6 cm.
Volume of the cone = \(\frac{1}{3}\) × π × 8 × 8 × 6 = 128π cm³
Difference in volume of the two solids = (128π – 96π) cm³ = 32π cm³ = 32 × \(\frac{22}{7}\) cm³ = 100.57 cm³
The difference in the volume of the two solids = 100.57 cm³

Question 6.
The volumes of two cones of same base radius are 3600 cm³ and 5040 cm³. Find the ratio of heights.
Answer:
Let the radius of the two cones be ‘r’
Let the height of the two cones be h₁ and h₂
Ratio of their volumes = 3600 : 5040 (÷ 10)
\(\frac{1}{3} \pi r^{2} h_{1}: \frac{1}{3} \pi r^{2} h_{2}\) = 360 : 504 (÷4)
h₁ : h₂ = 90 : 126 (÷3)
= 30 : 42 (÷3)
= 10 : 14 (÷2)
h₁ : h₂ = 5 : 7
Ratio of heights = 5 : 7

Question 7.
If the ratio of radii of two spheres is 4 : 7, find the ratio of their volumes.
Answer:
Let the ratio of their radii is r₁ : r₂
r₁ : r₂ = 4 : 7
Ratio of their volumes
V₁ : V₂ = \(\frac{4}{3} \pi r_{1}^{3}: \frac{4}{3} \pi r_{2}^{3}\)
= \(r_{1}^{3}: r_{2}^{3}\)
= 43 : 73
Ratio of their volumes = 64 : 343

Question 8.
A solid sphere and a solid hemisphere have an equal total surface area. Prove that the ratio of their volume is 3√3 : 4.
Answer:
Total surface area of a sphere = \(4 \pi r_{1}^{2}\) sq. units
Total surface area of a hemisphere = \(3 \pi r_{2}^{2}\) sq. units
Ratio of Total surface area = \(4 \pi r_{1}^{2}: 3 \pi r_{2}^{2}\)
1 = \(\frac{4 \pi r_{1}^{2}}{3 \pi r_{2}^{2}}\) (Same Surface Area)
1 = \(\frac{4 r_{1}^{2}}{3 r_{2}^{2}}\)

Ratio of their volumes = 3√3 : 4
Hence it is proved.

Question 9.
The outer and the inner surface areas of a spherical copper shell are 576π cm² and 324π cm² respectively. Find the volume of the material required to make the shell.
Answer:
Outer surface area of a spherical shell = 576π cm²
4πR² = 576π
4 × R² = 576
R² = \(\frac{576}{4}\) = 144
R = √144 = 12 cm
Inner surface area of a spherical shell = 324π cm²
4πr² = 324π
4r² = 324
r² = 81
r = √81 = 9
Volume of the material required = Volume of the hollow hemisphere = \(\frac{4}{3}\) π(R³ – r³) cm³

Volume of the material required = 4186.29 cm³

Question 10.
A container open at the top is in the form of a frustum of a cone of height 16 cm with radii of its lower and upper ends are 8 cm and 20 cm respectively. Find the cost of milk which can completely fill a container at the rate of ₹ 40 per litre.
Answer:
Height of the frustrum (h) = 16 cm
Radius of the upper part (R) = 20 cm
Radius of the lower part (r) = 8 cm
Volume of the frustum

Cost of milk in the container = 10.459 × 40 = ₹ 418.36
Cost of the milk = ₹ 418.36

Students can Download Tamil Nadu 11th Maths Model Question Paper 3 English Medium Pdf, Tamil Nadu 11th 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 11th Maths Model Question Paper 3 English Medium

General 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 one or two sentences.
6. Question numbers 31 to 40 in Part III are three-mark questions. These are to be answered in above three to five short sentences.
7. Question numbers 41 to 47 in Part IV are five-mark questions. These are to be answered in detail Draw diagrams wherever necessary.

Time: 2:30 Hours
Maximum Marks: 90

PART – 1

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

Question 1.
Let R be the universal relation on a set X with more than one element then R is ………………
(a) Not reflexive
(b) Not symmetric
(c) Transitive
(d) None of the above
Answer:
(c) Transitive

Question 2.
The value of log_ab log_bc log_ca is …………………..
(a) 2
(b) 1
(c) 3
(d) 4
Answer:
(b) 1

Question 3.
If log \(\log _{\sqrt{ }}\) 0.25 = 4 then the value of x is ………………..
(a) 0.5
(b) 2.5
(c) 1.5
(d) 1.25
Answer:
(a) 0.5

Question 4.
The product of r consecutive positive integers is divisible by ………………..
(a) r!
(b) (r-1)!
(c) (r+l)!
(d) r^r
Answer:
(a) r!

Question 5.
The value of tan75° – cot 75° is ……………….
(a) 1
(b) 2 + \(\sqrt{3}\)
(c) 2 – \(\sqrt{3}\)
(d) 2\(\sqrt{3}\)
Answer:
(d) 2\(\sqrt{3}\)

Question 6.
If (1 +x²)²(1 + x)² = a₀ + a₁ x + a₂x² …. + xⁿ⁺⁴ and if a₀, a₁, a₂, are in AP, then n is …………………..
(a) 1
(b) 2
(c) 3
(d) 4
Answer:
(c) 3

Question 7.
If _nC₁₂ = _nC₅ then _nC₂ = …………………
(a) 72
(b) 306
(c) 152
(d) 153
Answer:
(d) 153

Question 8.
The line (p + 2q)x + (p- 3q)y =p – q for different values of p and q passes through the point …………………
(a) (\(\frac{3}{5}\), \(\frac{2}{5}\))
(b) (\(\frac{2}{5}\), \(\frac{2}{5}\))
(c) (\(\frac{3}{5}\), \(\frac{3}{5}\))
(d) (\(\frac{2}{5}\), \(\frac{3}{5}\))
Answer:
(d) (\(\frac{2}{5}\), \(\frac{3}{5}\))

Question 9.
The number of terms in the expansion of [(a + b)²]¹⁸ = ………………..
(a) 19
(b) 18
(c) 36
(d) 37
Answer:
(d) 37

Question 10.
A line passes through the point (2, 2) and is perpendicular to the line 3x + y = 5 then its y intercept is …………………
Answer:
(a) \(\frac{3}{4}\)
(b) \(\frac{4}{3}\)
(c) 5
(d) \(\frac{1}{3}\)

Question 11.
If a and b are the roots of the equation x² – kx + 16 = 0 satisfy a² + b² = 32, then the value of k is ………………..
(a) 10
(b) -8
(c) -8, 8
(d) 6
Answer:
(c) -8, 8

Question 12.
If A is a square matrix of order 3 then |kA| = ………………….
(a) k |A|
(b) k²|A|
(c) k³|A|
(d) k|A³|
Answer:
(c) k³|A|

Question 13.
If ABCD is a parallelogram then \(\bar { AB } \) + \(\bar { AD } \) + \(\bar { CD } \) + \(\bar { CD } \) = ………………..
(a) 2(\(\bar { AB } \) + \(\bar { AD } \))
(b) 4\(\bar { AC } \)
(c) 4\(\bar { BD } \)
(d) \(\bar { o } \)
Answer:
(d) \(\bar { o } \)

Question 14.
\(\lim _{x \rightarrow 0}\) x cot x = ………………….
(a) 0
(b) 1
(c) -1
(d) ∞
Answer:
(b) 1

Question 15.
If x = \(\frac { 1-t^{ 2 } }{ 1+t^{ 2 } } \) and y = \(\frac { 2t }{ 1+t^{ 2 } } \) then \(\frac{dy}{dx}\) = ………………..
(a) \(\frac{y}{x}\)
(b) \(\frac{-y}{x}\)
(c) –\(\frac{x}{y}\)
(d) \(\frac{x}{y}\)
Answer:
(c) –\(\frac{x}{y}\)

Question 16.
If y = \(\frac { (1-x)^{ 2 } }{ x^{ 2 } } \) then \(\frac{dy}{dx}\) is …………………..
(a) \(\frac { 2 }{ x^{ 2 } } \) + \(\frac { 2 }{ x^{ 3 } } \)
(b) –\(\frac { 2 }{ x^{ 2 } } \) + \(\frac { 2 }{ x^{ 3 } } \)
(c) –\(\frac { 2 }{ x^{ 2 } } \) – \(\frac { 2 }{ x^{ 3 } } \)
(d) –\(\frac { 2 }{ x^{ 3 } } \) + \(\frac { 2 }{ x^{ 2 } } \)
Answer:
(d) –\(\frac { 2 }{ x^{ 3 } } \) + \(\frac { 2 }{ x^{ 2 } } \)

Question 17.
If y = \(\frac{sinx+cosx}{sinx-cosx}\) then \(\frac{dy}{dx}\) at x = \(\frac { \pi }{ 2 } \) is ………………….
(a) 1
(b) 0
(c) -2
(d) 2
Answer:
(c) -2

Question 18.
\(\int \frac{\sin ^{8} x-\cos ^{8} x}{1-2 \sin ^{2} x \cos ^{2} x}\) dx is ……………………
(a) \(\frac{1}{2}\) sin2x + c
(b) –\(\frac{1}{2}\) sin2x + c
(c) \(\frac{1}{2}\) cos 2x + c
(d) – \(\frac{1}{2}\) cos 2x + c
Answer:
(b) –\(\frac{1}{2}\) sin2x + c

Question 19.
An urn contains 5 red and 5 black balls. A balls is drawn at random, its colour is noted and is returned to the urn. Moreover, 2 additional balls of the colour drawn are put in the urn and then a ball is drawn at random. The probability that the second ball drawn is red will be ………………
(a) \(\frac{5}{12}\)
(b) \(\frac{1}{2}\)
(c) \(\frac{7}{12}\)
(d) \(\frac{1}{4}\)
Answer:
(b) \(\frac{1}{2}\)

Question 20.
Let A and B be two events such that P(\(\bar { AUB } \)) = \(\frac{1}{6}\) , Then the events A and B are P(A∩B) = 1/4 and P(\(\bar { A } \)) = 1/4 is ………………
(a) Equally likely but not independent
(b) Independent but not equally likely
(c) Independent and equally likely
(d) Mutually inclusive and dependent
Answer:
(b) Independent but not equally likely

PART – II

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

Question 21.
Let A and B are two sets such that n(A) = 3 and n(B) = 2. If (x, 1), (y, 2) and (z, 1) are in A × B, find A and B where x, y, z are distinct elements?
Answer:
n(A) = 3 ⇒ set A contains 3 elements
n(B) = 2 ⇒ set B contains 2 elements
we are given (x, 1), (y, 2), (z, 1) are elements in A × B
⇒ A = {x, y, z} and B = {1, 2}

Question 22.
Solve |5x — 12| ← 2
Answer:
5x – 12 > -2 (or) 5x – 12 < 2 ⇒ 5x > -2 + 12 (= 10)
⇒ x > \(\frac{10}{5}\) = 2
x > 2
(or)
5x < 2 + 12 (= 14)
⇒ x < \(\frac{14}{5}\)
so 2 < x < \(\frac{14}{5}\)

Question 23.
If ¹⁰P_r-1 = 2 × 6 P_r, find r?
Answer:
¹⁰P_r-1 = 2 × 6P_r

⇒ (11 – r) (10 – r) (9 – r) (8 – r) (7 – r) = 10 × 9 × 4 × 7
= 5 × 2 × 3 × 3 × 2 × 2 × 7
= 7 × 6 × 5 × 4 × 3
⇒ 11 – r = 7
11 – 7 = r
r = 4

Question 24.
The number of bacteria in a certain culture doubles every hour. If there were 30 bacteria present in the culture originally, how many bacteria will be present at the end of 2^nd hour, 4^th hour and n^th hour?
Answer:
No. of bacteria at the beginning = 30
No. of bacteria after 1 hour = 30 × 2 = 60
No. of bacteria after 2 hours = 30 × 2² = 30 × 4 = 120
No. of bacteria after 4 hours = 30 × 2⁴ = 30 × 16 = 480
No. of bacteria after n^th hour = 30 × 2ⁿ

Question 25.
Find |A| if A = \(\left[\begin{array}{ccc}
0 & \sin \alpha & \cos \alpha \\
\sin \alpha & 0 & \sin \beta \\
\cos \alpha & -\sin \beta & 0
\end{array}\right]\)
Answer:
\(\left[\begin{array}{ccc}
0 & \sin \alpha & \cos \alpha \\
\sin \alpha & 0 & \sin \beta \\
\cos \alpha & -\sin \beta & 0
\end{array}\right]\)
= 0M₁₁ – sin αM₁₂ + cos αM₁₃
= 0 – sin α(0 – cos α sin β) + cos α(- sin α sin β – 0) = 0

Question 26.
Find the value of λ for which the vectors \(\vec { a } \) = 3\(\hat { i } \) + 2\(\hat { j } \) + 9\(\hat { k } \) and \(\vec { a } \) = \(\hat { i } \) + λ\(\hat { j } \) +3\(\hat { k } \) are parallel?
Answer:
Given \(\vec { a } \) and \(\vec { b } \) are parallel ⇒\(\vec { a } \) = t\(\vec { b } \) (where t is a scalar)
(i.e.,) 3\(\hat { i } \) + 2\(\hat { j } \) + 9\(\hat { k } \) = t\(\hat { i } \) + λ\(\hat { j } \) + 3\(\hat { k } \))
equating \(\hat { i } \) components we get 3 = t
equating \(\hat { j } \) components
(i.e); 2 = tλ
2 = 3λ ⇒λ = 2/3

Question 27.
Evaluate \(\underset { x\rightarrow \pi }{ lim } \) \(\frac{sin 3x}{sin 2x}\)
Answer:

Question 28.
Find the derivative of sinx² with respect to x²?
Answer:

Question 29.
Let the matrix M = \(\begin{bmatrix} x & y \\ z & 1 \end{bmatrix}\) if x, y and z are chosen at random from the set {1, 2, 3}, and repetition is allowed (i.e., x = y = z), what is the probability that the given matrix M is a singular matrix?
Answer:
If the given matnx M is singular, then = \(\begin{vmatrix} x & y \\ z & 1 \end{vmatrix}\) = 0
That is, x – yz = 0
Hence the possible ways of selecting (x, y, z) are
{(1, 1, 1), (2, 1, 2), (2, 2, 1), (3, 1, 3), (3, 3, 1)} = A (say)
The number of favourable cases n(A) = 5
The total number of cases are n(S) = 3³ = 27
The probability of the given matrix is a singular matrix is
P(A) = \(\frac{n(A)}{n(S)}\) = \(\frac{5}{27}\)

Question 30.
Evaluate \(\frac { x^{ 2 } }{ 1+x^{ 6 } } \)
Answer:

PART – III

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

Question 31.
If f, g, h are real valued functions defined on R, then prove that (f + g) o h = f o h + g o h. What can you say about fo(g + h)? Justify your answer?

Question 32.
Solve \(\frac{4}{x+1}\) ≤ 3 ≤ \(\frac{6}{x+1}\), x > 0?

Question 33.
Prove that cos^-1 \(\frac{4}{5}\) + tan^-1 \(\frac{3}{5}\) = tan^-1 \(\frac{27}{11}\)?

Question 34.
There are 15 candidates for an examination. 7 candidates are appearing for mathematics examination while the remaining 8 are appearing for different subjects. In how many ways
can they be seated in a row so that no two mathematics candidates are together?

Question 35.
Prove that if a, b, c are in H.P. if and only if \(\frac{a}{c}\) = \(\frac{a-b}{b-c}\)?

Question 36.
If (-4, 7) is one vertex of a rhombus and if the equation of one diagonal is 5x – y + 7 = 0, then find the equation of another diagonal?

Question 37.
Verify the existence of \(\underset { x\rightarrow 1 }{ lim } \) f(x), where f(x) = \(\left\{\begin{aligned}
\frac{|x-1|}{x-1}, & \text { for } x \neq 1 \\
0, & \text { for } x=1
\end{aligned}\right.\)

Question 38.
If y = sin^-1 x then find y?

Question 39.
Evaluate cot² x + tan² x?

Question 40.
Show that
\(\left|\begin{array}{ccc}
2 b c-a^{2} & c^{2} & b^{2} \\
c^{2} & 2 c a-b^{2} & a^{2} \\
b^{2} & a^{2} & 2 a b-c^{2}
\end{array}\right|=\left|\begin{array}{ccc}
a & b & c \\
b & c & a \\
c & a & b
\end{array}\right|^{2}\)

PART – IV

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

Question 41 (a).
The total cost of airfare on a given route is comprised of the base cost C and the fuel surcharge S in rupee. Both C and S are functions of the mileage m; C(m) = 0.4m + 50 and S(m) = 0.03m. Determine a function for the total cost of a ticket in terms of the mileage and find the airfare for flying ¡600 miles?

[OR]

(b) Evaluate \(\sqrt { x^{ 2 }+x+1 } \)?

Question 42 (a).
Determine the region in the plane determined by the inequalities y ≥ 2x and -2x + 3y ≤ 6?

[OR]

(b) If y(cos^-1 x)², prove that (1-x²) \(\frac { d^{ 2 }y }{ dx^{ 2 } } \) – x \(\frac{dy}{dx}\) – 2 = 0. Hence find y₂ when x = 0?

Question 43(a).
Prove that ⁿC_r + ⁿC_r-1 = ⁿ⁺¹C_r

[OR]

(b) If the binomial coefficients of three consecutive terms in the expansion of (a + x)ⁿ are in the ratio 1 : 7 : 42, then find n?

Question 44 (a).
(a) Prove that

1. sin A + sin( 120° + A) + sin (240° + A) = O
2. cos A+ cos (120° + A) + cos (120° – A) = O

[OR]

(b) A box contains two white balls, three black balls and four red balls. In how many ways can three balls be drawn from the box, if at least one black ball is to be included in the draw?

Question 45 (a).
Show that \(\left|\begin{array}{ccc}
a^{2}+x^{2} & a b & a c \\
a b & b^{2}+x^{2} & b c \\
a c & b c & c^{2}+x^{2}
\end{array}\right|\) is divisible by x⁴?

[OR]

(b) \(\left[\begin{array}{ccc}
0 & p & 3 \\
2 & q^{2} & -1 \\
r & 1 & 0
\end{array}\right]\) is skew-symmetric, find the values of p, q and r?

Question 46 (a).
In a shopping mall there is a hail of cuboid shape with dimension 800 × 800 × 720 units, which needs to be added the facility of an escalator in the path as shown by the dotted line in the figure. Find

1. The minimum total length of the escalator
2. The heights at which the escalator changes its direction
3. The slopes of the escalator at the turning points.

[OR]

(b) Evaluate \(\lim _{x \rightarrow a} \frac{\sqrt{x-b}-\sqrt{a-b}}{x^{2}-a^{2}}(a>b)\)

Question 47 (a).
Evaluate ∫\(\frac { 3x+5 }{ x^{ 2 }+4x+7 } \) dx

[OR]

(b) A factory has two Machines – I and II. Machine-I produces 60% of items and Machine-II produces 40% of the items of the total output. Further 2% of the items produced by Machine-I are defective whereas 4% produced by Machine-II are defective. If an itci is drawn at random what is the probability that it is defective?

Students can download Maths Chapter 7 Mensuration Ex 7.1 Questions and Answers, Notes, Samacheer Kalvi 10th Maths Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 10th Maths Solutions Chapter 7 Mensuration Ex 7.1

Question 1.
The radius and height of a cylinder are in the ratio 5 : 7 and its curved surface area is 5500 sq.cm. Find its radius and height.
Answer:
Let the radius be 5x and the height be 7x
C.S.A of a cylinder = 5500 sq.cm.
2πrh = 5500
2 × \(\frac{22}{7}\) × 5x × 7x = 5500
2 × 22 × 5 × x² = 5500
x² = \(\frac{5500}{2 \times 22 \times 5}\)
x² = 25 cm
x = 5 cm
Radius of the cylinder = 5 × 5 = 25 cm
Height of the cylinder = 7 × 5 = 35 cm

Question 2.
A solid iron cylinder has total surface area of 1848 sq.m. Its curved surface area is five-sixth of its total surface area. Find the radius and height of the iron cylinder.
Answer:
T.S.A of the cylinder =1848 sq.cm
2πr(h + r) = 1848 ……. (1)
Curved surface area = \(\frac{5}{6}\) × 1848 sq.cm
2πrh = 5 × 308
2πrh = 1540 sq.m ……… (2)
Substitute the value of2πrh in (1)
2πr(h + r) = 1848
2πrh + 2πr² = 1848
1540 + 2πr² = 1848
2πr² = 1848 – 1540
2 × \(\frac{22}{7}\) × r² = 308
r² = \(\frac{308 \times 7}{2 \times 22}\) = 49
r = 7
Radius of the cylinder = 7m
2πrh = 1540
2 × \(\frac{22}{7}\) × 7 × h = 1540
h = \(\frac{1540}{2 \times 22}\) = 35 m
Radius of the cylinder = 7 m
Height of the cylinder = 35 m

Question 3.
The external radius and the length of a hollow wooden log are 16 cm and 13 cm respectively. If its thickness is 4 cm then find its T.S.A.
Answer:
External radius of the wooden log (R) = 16 cm
Thickness = 4 cm
Internal radius (r) = 16 – 4 = 12 cm
Length of the wooden log (h) = 13 cm
T.S.A of the hollow cylinder = 2π (R + r) (R – r + h) sq.cm
= 2 × \(\frac{22}{7}\) × (16 + 12) (16 – 12 + 13) sq.cm
= 2 × \(\frac{22}{7}\) × 28 × 17 sq.cm
= 2 × 22 × 4 × 17 sq.cm.
= 2992 sq.cm.
T.S.A of the hollow wooden = 2992 sq.cm.

Question 4.
A right angled triangle PQR where ∠Q = 90° is rotated about QR and PQ. If QR = 16 cm and PR = 20 cm, compare the curved surface areas of the right circular cones so formed by the triangle.
Answer:

In the Right Triangle
QP² = PR² – QR²= 20² – 16² = 400 – 256 = 144
QP = √144 = 12 cm
When PQ is rotated r = 12, l = 20
C.S.A of the cone = πrl sq. units = π × 12 × 20 cm² = 240π cm²
When QR is rotated r = 16, l = 20
C.S.A of the cone = nrl sq. units = π × 16 × 20 = 320π cm²
C.S.A. of a cone when rotated about QR is larger.

Question 5.
4 persons live in a conical tent whose slant height is 19 cm. If each person requires 22 cm² of the floor area, then find the height of the tent.
Answer:
Slant height of a cone (r) = 19 cm
Floor area for 4 persons = 4 × 22 cm²
πr² = 88 cm

Height of the tent = 18.25 cm

Question 6.
A girl wishes to prepare birthday caps in the form of right circular cones for her birthday party, using a sheet of paper whose area is 5720 cm², how many caps can be made with radius 5 cm and height 12 cm.
Answer:
Radius of a cap (r) = 5 cm

Question 7.
The ratio of the radii of two right circular cones of the same height is 1 : 3. Find the ratio of their curved surface area when the height of each cone is 3 times the radius of the smaller cone.
Answer:
Let the radius of the first cone be ‘x’ and the Height of the cone be 3x

Question 8.
The radius of a sphere increases by 25%. Find the percentage increase in its surface area.
Answer:
Let the radius of the be “r”
Surface area of the sphere = 4πr² sq.units …….. (1)
If the radius is increased by 25%



Percentage of increase in surface area = 56.25 %

Question 9.
The internal and external diameters of a hollow hemispherical vessel are 20 cm and 28 cm respectively. Find the cost to paint the vessel all over at ₹ 0.14 per cm².
Answer:

Question 10.
The frustum shaped outer portion of the table lamp has to be painted including the top part. Find the total cost of painting the lamp if the cost of painting 1 sq.cm is ₹ 2.

Answer:
The slant height of the frustum (l)


Cost of painting = ₹ 678.86 × 2 = ₹ 1357.72

Students can download 6th Social Science Term 1 Civics Chapter 1 Understanding Diversity Questions and Answers, Notes, Samacheer Kalvi 6th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 6th Social Science Civics Solutions Term 1 Chapter 1 Understanding Diversity

Samacheer Kalvi 6th Social Science Understanding Diversity Text Book Back Questions and Answers

A. Choose the correct answer

Question 1.
India consists of ……………. states and ……………. Union territories.
(a) 27,9
(b) 29,7
(c) 28,7
(d) 28,9
Answer:
(b) 29,7

Question 2.
India is known as a
(a) Continent
(b) Subcontinent
(c) Island
(d) None of these
Answer:
(b) Sub continent

Question 3.
Mawsynram, the land of highest rainfall is located in …………….
(a) Manipur
(b) Sikkim
(c) Nagaland
(d) Meghalaya
Answer:
(d) Meghalaya

Question 4.
Which one of the following religion is not practised in India
(a) Sikhism
(b) Islam
(c) Zoroastrianism
(d) Confucianism
Answer:
(d) Confucianism

Question 5.
Recognised official languages of India, as per VUIth schedule of Indian constitution …………….
(a) 25
(b) 23
(c) 22
(d) 26
Answer:
(c) 2

Question 6.
Onam festival celebrated in
(a) Kerala
(b) Tamil Nadu
(c) Punjab
(d) Karnataka
Answer:
(a) Kerala

Question 7.
Mohiniyattam is a classical dance of …………….
(a) Kerala
(b) Tamil Nadu
(c) Manipur
(d) Karnataka
Answer:
(a) Kerala

Question 8.
Discovery of India’ a book was written by
(a) Rajaji
(b) V.O.C
(c) Nethaji
(d) Jawaharlal Nehru
Answer:
(d) Jawaharlal Nehru

Question 9.
The phrase ‘Unity in Diversity’ was coined by …………….
(a) Jawaharlal Nehru
(b) Ambedkar
(c) Mahathma Gandhi
(d) Rajaji
Answer:
(a) JawahalalNehru

Question 10.
V.A. Smith called India as __________
(a) Great Democracy
(b) Unique land of diversities
(c) Ethnological museum
(d) Secular nation
Answer:
(c) Ethnological museum

II. Fill in the blanks

1. Geographical features and climatic conditions determine the ……………. activities of a region.
2. Jaisalmer, the land of lowest rainfall is located in …………….
3. Tamil was declared as classical language in the year …………….
4. Bihu festival is celebrated in …………….

Answer:

1. economic
2. Rajasthan
3. 2004
4. Assam

III. Match the following

Answer:
1. – d
2. – c
3. – a
4. – b

IV. Answer the following questions

Question 1.
Define diversity.
Answer:
We, the Indians come from different backgrounds, belong to different cultures, worship in different ways. This is known as diversity.

Question 2.
What are the types of diversity?
Answer:

1. Landform and lifestyle diversity
2. Social diversity
3. Religious diversity
4. Linguistic diversity
5. Cultural diversity

Question 3.
Why is India called a subcontinent?
Answer:
A continent is a very large area of land with various physical features such as mountains, plateaus, plains, rivers and seas, and various types of weather patterns. India has all of them. So India is known as a subcontinent.

Question 4.
Write the names of three major festivals celebrated in India.
Answer:

1. Deepavali
2. Christmas
3. Ramzan

Question 5.
List out some of the classical dances of India,
Answer:

1. Tamil Nadu – Bharatanatyam
2. Kerala – Kathakali
3. Karnataka – Yakshagana
4. Odisha – Odissi
5. Andhra Pradesh – Kuchipudi
6. Manipur – Manipuri
7. Assam – Sattriya

Question 6.
Why is India called the land of unity in diversity?
Answer:
Though diversity is visible in every aspect of life in India, we are united by the spirit of patriotism.

V. Answer the following in detail

Question 1.
Explain Linguistic diversity and cultural diversity.
Answer:
Linguistic Diversity:

1. According to the census of India 2001, India has 122 major languages and 1599 other languages.
2. Four major Indian language families are Indo-Aryan, Dravidian, Austroasiatic, and Sino Tibetian. Tamil is the oldest Dravidian language.
3. Historically, the Portuguese, the Dutch, the British, the Danish and the French came to India for trade and their occupation of India or some parts of it has left behind a certain impact upon the culture and language of the people.
4. In due course, English has emerged as an important language and a medium of instruction in schools and colleges.
5. (It is widely used in official communication and daily life.

Cultural Diversity:

1. The term ‘culture’ refers to the customs and practices of people, their language, their dress code, cuisine, religion, social habits, music, art, and architecture.
2. The culture of a group of people is reflected in their social behaviour and interactions.
3. The group identity fostered by social patterns is unique to a group.
4. Art and architecture are an integral part of every community.
5. It develops as a part of the culture and tradition of a community.

Question 2.
“‘India is a land of diversity, yet we are all united”. Explain.
Answer:

1. Diversity is visible in every aspect of life in India.
2. Even then, we are united by the spirit of patriotism.
3. Symbols such as the National Flag and National Anthem remind us of our great nation and need to stay united.
4. We come together when we celebrate Independence Day, Republic Day and Gandhi Jayanthi every year.
5. India has a multi-cultural society.
6. India evolved as a single nation through common beliefs, customs, and cultural practices.
7. The freedom struggle and the drafting of our constitution stand as ample evidence , to the spirit of unity of India.

VI. Projects and Activities (For Students)

1. “The occupation of people depends on the landform of a place” Give some examples.
2. Read about a state of your choice and make an album to show the culture and tradition of people who live in that state.
3. Collect the pictures to show the and and architecture of Tamilnadu.

VII. HOTS

List out the various festivals celebrated in different states.

VIII. Life Skill

Suggest measures to bring unity in your school.

1. Uniform dress
2. Celebrating festivals of all religions.
   • Deepavali
   • Christmas
   • Ramzan
   • Pongal
3. Conducting community prayers.
4. Inter – dining
5. Celebration of School Day
6. Other extracurricular activities.
7. Conducting L.D.S meetings.

Samacheer Kalvi 6th Social Science Understanding Diversity Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
The oldest Dravidian language is …………….
(a) Hindi
(b) Tamil
(c) Sanskrit
(d) Telugu
Answer:
(b) Tamil

Question 2.
Punjab is well-known as for_______ dance.
(a) Bihu
(b) Dandia
(c) Bhangra
(d) Dumhal
Answer:
(c) Bhangra

Question 3.
Tamil was declared as a classical language in …………….
(a) 2002
(b) 2004
(c) 2012
(d) 2008
Answer:
(b) 2004

II. Fill in the blanks

1. Gurunanak Jayanthi is celebrated by the ……………..
2. India became independent in the year ……………..
3. The first Prime Minister of independent India is ……………..
4. The fundamental unit of a society is the ……………..
5. The folk dance of Punjab is ……………..

Answer:

1. Sikhs
2. 1947
3. Jawaharlal Nehru
4. Family
5. Bhangra

III. Answer in brief

Question 1.
What is meant by family? What are the types of the family?
Answer:
Family is the fundamental unit of society. Joint families and nuclear families are the two types of families.

Question 2.
Define community.
Answer:
Our community is made up of peasants, labourers, artisans, parents, teachers, students, and many others.

Question 3.
What is a continent?
Answer:
A continent is a very large area of land with various physical features such as mountains, plateaus, plains, rivers and seas and various types of weather patterns.

Question 4.
Name the religions which flourish in India.
Answer:
Hinduism, Islam, Christianity, Sikhism, Buddhism, Jainism and Zoroastrianism flourish in India.

Question 5.
Mention the religions of India.
Answer:

1. Hinduism
2. Islam
3. Christianity
4. Sikhism
5. Buddhism
6. Jainism and Zoroastrianism are the religion of India.

Question 6.
Mention the people who came to India for trade.
Answer:
The Portuguese, the Dutch, the British, the Danish and the French came to India for trade.

Question 7.
Mention any four folk dances of India.
Answer:

1. Tamil Nadu – Karagattam, Oyillattam, Kummi, Thappattam
2. Kerala – Mohiniattam
3. Punjab – Bhangra
4. Gujarat – Dandia

IV. Mind Map

Students can Download Tamil Nadu 11th Maths Model Question Paper 2 English Medium Pdf, Tamil Nadu 11th 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 11th Maths Model Question Paper 2 English Medium

General 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 one or two sentences.
6. Question numbers 31 to 40 in Part III are three-mark questions. These are to be answered in above three to five short sentences.
7. Question numbers 41 to 47 in Part IV are five-mark questions. These are to be answered in detail Draw diagrams wherever necessary.

Time: 2:30 Hours
Maximum Marks: 90

PART – 1

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

Question 1.
Let R be the set of all real numbers. Consider the following subsets of the plane R × R:
S= {(x, y) : y = x + 1 and 0 < x < 2} and T = {(x, y): x – y is an integer}
Then which of the following is true?
(a) T is an equivalence relation but S is not an equivalence relation.
(b) Neither S nor T is an equivalence relation
(c) Both S and T are equivalence relation
(d) S is an equivalence relation but T is not an equivalence relation.
Answer:
(a) T is an equivalence relation but S is not an equivalence relation.

Question 2.
If the set A has m elements the set B has n elements and the number of elements in A × B is …………………
(a) m + n
(b) mn
(c) \(\frac{m}{n}\)
(d) m²
Answer:
(b) mn

Question 3.
If \(\frac{ax}{(x+2)(2x-3)}\) = \(\frac{2}{x+2}\) + \(\frac{3}{2x-3}\) then a = ……………….
(a) 8
(b) 7
(c) 5
(d) 4
Answer:
(b) 7

Question 4.
The number of solutions of x² + |x – 1| = 1 is ………………….
(a) 1
(b) 0
(c) 2
(d) 3
Answer:
(c) 2

Question 5.
If a, 8, b are in A.P. a, 4, b are in G.P. and a, x, b are in H.P then x = ………………..
(a) 2
(b) 1
(c) 4
(d) 16
Answer:
(a) 2

Question 6.
If 10 lines are drawn in a plane such that no two of them are parallel and no three are concurrent, then the total number of points of intersection are ……………….
(a) 45
(b) 40
(c) 10!
(d) 2¹⁰
Answer:
(a) 45

Question 7.
The value of e^2logx = …………………..
(a) 2x
(b) x²
(c) \(\sqrt{x}\)
(d) \(\frac{x}{2}\)
Answer:
(b) x²

Question 8.
The n^th term of the sequence 1, 2, 4, 7, 11 …. is …………………
(a) n³ + 3n² + 2n
(b) n³ – 3n² + 3n
(c) n\(\frac{(n+1)(n+2)}{3}\)
(d) \(\frac { n^{ 2 }-n+2 }{ 2 } \)
Answer:
(d) \(\frac { n^{ 2 }-n+2 }{ 2 } \)

Question 9.
The last term in the expansion (2+\(\sqrt{3}\))⁸ is ………………
(a) 81
(b) 27
(c) 9
(d) 3
Answer:
(a) 81

Question 10.
A line perpendicular to the line 5x -y = 0 forms a triangle with the coordinate axes. If the area of the triangle is 5sq.units, then its equation is …………………..
(a) x + 5y ± 5\(\sqrt{2}\) = 0
(b) x – 5y ± 5\(\sqrt{2}\) = 0
(c) 5x + y ± 5\(\sqrt{2}\) = 0
(d) 5x – y ± 5\(\sqrt{2}\) = 0
Answer:
(a) x + 5y ± 5\(\sqrt{2}\) = 0

Question 11.
A factor of the determinant \(\left|\begin{array}{ccc}
x & -6 & -1 \\
2 & -3 x & x-3 \\
-3 & 2 x & x+2
\end{array}\right|\) is ……………….
(a) x + 3
(b) 2x – 1
(c) x – 2
(d) x – 3
Answer:
(a) x + 3

Question 12.
If λ\(\vec { a } \) + 2λ\(\vec { j } \) + 2λ\(\vec { k } \) is a unit vector then the value of λ is ………………
(a) \(\frac{1}{3}\)
(b) \(\frac{1}{4}\)
(c) \(\frac{1}{9}\)
(d) \(\frac{1}{2}\)
Answer:
(a) \(\frac{1}{3}\)

Question 13.
One of the diagonals of parallelogram ABCD with \(\vec { a } \) and \(\vec { b } \) are adjacent sides is \(\vec { a } \) + \(\vec { b } \). The other diagonal BD is ………………….
(a) \(\vec { a } \) – \(\vec { b } \)
(b) \(\vec { a } \) – \(\vec { b } \)
(c) \(\vec { a } \) + \(\vec { b } \)
(d) \(\frac{\vec{a}+\vec{b}}{2}\)
Answer:
(b) \(\vec { a } \) – \(\vec { b } \)

Question 14.
If (1, 2, 4) and (2, -3λ, -3) are the initial and terminal points of the vector \(\vec { i } \) + 5\(\vec { j } \) – 7\(\vec { k } \) then the value of λ …………………..
(a) \(\frac{7}{3}\)
(b) –\(\frac{7}{3}\)
(c) \(\frac{5}{3}\)
(d) \(\frac{-5}{3}\)
Answer:
(b) –\(\frac{7}{3}\)

Question 15.
If y = mx + c and f(0) =f'(0) = 1 then f(2) = …………………..
(a) 1
(b) 2
(c) 3
(d) 4
Answer:
(c) 3

Question 16.
The derivative of (x + \(\frac{1}{x}\))² w.r.to. x is ………………..
(a) 2x – \(\frac { 2 }{ x^{ 3 } } \)
(b) 2x + \(\frac { 2 }{ x^{ 3 } } \)
(c) 2(x + \(\frac{1}{x}\))
(d) 0
Answer:
(a) 2x – \(\frac { 2 }{ x^{ 3 } } \)

Question 17.
If f(x) is \(\left\{\begin{array}{cc}
a x^{2}-b, & -1<x<1 \\
\frac{1}{|x|}, & \text { elsewhere }
\end{array}\right.\) is differentiable at x = 1, then …………………
(a) a = \(\frac{1}{2}\), b = \(\frac{-3}{2}\)
(b) a = \(\frac{-1}{2}\), b = \(\frac{3}{2}\)
(c) a = \(\frac{-1}{2}\), b = \(\frac{-3}{2}\)
(d) a = \(\frac{1}{2}\), b = \(\frac{3}{2}\)
Answer:
(c) a = \(\frac{-1}{2}\), b = \(\frac{-3}{2}\)

Question 18.
∫\(\frac { \sqrt { tanx } }{ sin2x } \) dx is ………………
(a) \(\sqrt{tanx}\) + c
(b) 2\(\sqrt{tanx}\) + c
(c) \(\frac{1}{2}\) \(\sqrt{tanx}\) + c
(d) \(\frac{1}{4}\) \(\sqrt{tanx}\) + c
Answer:
(a) \(\sqrt{tanx}\) + c

Question 19.
An urn contains 5 red and 5 black balls. A balls is drawn at random, its colour is noted and is returned to the urn. Moreover, 2 additional balls of the colour drawn are put in the urn and then a ball is drawn at random. The probability that the second ball drawn is red will be ………………….
(a) \(\frac{5}{12}\)
(b) \(\frac{1}{2}\)
(c) \(\frac{7}{12}\)
(d) \(\frac{1}{4}\)
Answer:
(b) \(\frac{1}{2}\)

Question 20.
It is given that the events A and B are such that P(A) = \(\frac{1}{4}\), P(A/B) = \(\frac{1}{2}\), and P(B/A) = \(\frac{2}{3}\) then
P(B) = ………………….
(a) \(\frac{1}{6}\)
(b) \(\frac{1}{3}\)
(c) \(\frac{2}{3}\)
(d) \(\frac{1}{2}\)
Answer:
(b) \(\frac{1}{3}\)

PART – II

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

Question 21.
If n(P(A)) = 1024, n(A∪B) = 15 and n(P(B)) = 32 then find n(A∩B)
Answer:
n(P(A)) = 1024 = 2¹⁰ ⇒ n(A) = 10
n(A∪B) = 15
n(P(B)) = 32 = 2⁵ ⇒ n(B) = 5
We know n(A∪B) = n(A) + n(B) – n(A∩B)
(i.e) 15 = 10 + 5 – n(A∩B)
⇒ n(A∩B) = 15 – 15 = 0

Question 22.
Simplify (343)^2/3
Answer:
(343)^2/3 = (7³)^2/3 = 7^3×2/3 = 7² = 49

Question 23.
Show that cos36° cos 72° cos 108° cos 144° = \(\frac{1}{16}\)
Answer:
LHS = cos36° cos(90° – 18°) cos(90° – 18°) cos(90° + 18°) cos(180° – 36°)
= sin² 18° cos² 36°
= (\(\frac { \sqrt { 5-1 } }{ 4 } \))² (\(\frac { \sqrt { 5+1 } }{ 4 } \))² = \(\frac{1}{16}\) = RHS

Question 24.
Find the number of ways of selecting 9 balls from 6 red balls, 5 white balls and 5 blue balls if each selection consists of 3 balls of each colour?
Answer:
There are 6 red balls, 5 white balls and 5 blue balls.
We have to select 3 balls of each colour.
∴Number of ways of selection = ⁶C₃ × ⁵C₃ × ⁵C₃
= \(\frac { 6! }{ 3!3! } \) × \(\frac { 5! }{ 3!2! } \) × \(\frac { 5! }{ 3!2! } \)
= 20 × 10 × 10 = 2000

Question 25.
Find |A| if A = \(\left[\begin{array}{ccc}
0 & \sin \alpha & \cos \alpha \\
\sin \alpha & 0 & \sin \beta \\
\cos \alpha & -\sin \beta & 0
\end{array}\right]\)
Answer:
\(\left[\begin{array}{ccc}
0 & \sin \alpha & \cos \alpha \\
\sin \alpha & 0 & \sin \beta \\
\cos \alpha & -\sin \beta & 0
\end{array}\right]\)
= 0M₁₁ – sin αM₁₂ + cos αM₁₃
= 0 – sin α(0 – cos α sin β) + cos α (-sin α sin β – 0) = 0

Question 26.
For any vector prove that \(\vec { r } \) = [\(\vec { r } \).\(\vec { i } \)) + (\(\vec { r } \).\(\vec { j } \))j + [\(\vec { r } \).\(\vec { k } \)}k
Answer:
Let \(\vec { r } \) = x\(\hat { i } \) + y\(\hat { j } \) + z\(\hat { k } \)

Question 27.
Calculate \(\lim _{x \rightarrow-2}\) (x³ – 3x + 6) (-x² + 15)
Answer:

Question 28.
Evaluate y = e^x sin x
Answer:

Question 29.
Integrate the following with respect to x
\(\frac{4}{3+4x}\) + (10x + 3)⁹ – 3 cosec(2x + 3) cot (2x + 3)
Answer:

Question 30.
P(A) = 0.6, P (B) = 0.5 and P(A∩B) = 0.2 find P(A/B)
Answer:
Given that P(A) = 0.6, P(B) = 0.5, and P(A∩B) = 0.2
P(A/B) = \(\frac { p(A∩B) }{ p(B) } \) = \(\frac{0.2}{0.5}\) = \(\frac{2}{5}\)

PART – III

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

Question 31.
A quadratic polynomial has one of its zeros 1 + \(\sqrt{5}\) and it satisfies p(1) = 2. Find the quadratic polynomial?

Question 32.
Prove that

1. tan^-1 (\(\frac{1}{7}\)) + tan^-1(\(\frac{1}{13}\)) = tan^-1(\(\frac{2}{9}\))
2. cos^-1\(\frac{4}{5}\) + tan^-1\(\frac{3}{5}\) = tan^-1\(\frac{27}{11}\)

Question 33.
The product of three increasing numbers in GP is 5832. If we add 6 to the second number and 9 to the third number, then resulting numbers form an AP. Find the numbers in GP?

Question 34.
Find the equation of the line passing through the point (5, 2) and perpendiular to the line joining the points (2, 3) and (3, -1)?

Question 35.
Find the area of the triangle whose vertices are (0,0), (1,2) and (4,3)?

Question 36.
If \(\vec { a } \), \(\vec { b } \), \(\vec { c } \) are three vectors such that \(\vec { a } \) + 2\(\vec { b } \) + \(\vec { c } \) = 0 and |\(\vec { a } \)| = 3, |\(\vec { b } \)| = 4, |\(\vec { c } \)| = 7 fimd the angle between \(\vec { a } \) and \(\vec { b } \)

Question 37.
Evaluate: \({ \underset { x\rightarrow 0 }{ lim } }\) \(\frac { 3^{ x }-1 }{ \sqrt { 1+x-1 } } \)

Question 38.
Find \(\frac{dy}{dx}\) for y = tan^-1 \((\frac { cosx+sinx }{ cosx-sinx } )\)

Question 39.
Evaluate: ∫x⁵ e^x2

Question 40.
How many automobile license plates can be made, if each plate contains two different letters followed by three different digits?

PART – IV

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

Question 41.
(a) If f : R – {-1, 1} → R is defined by f(x) = \(\frac { x }{ x^{ 2 }-1 } \), verify whether f is one-to-one or not?

[OR]

(b) Solve: log₂ x + log₄ x + log₈ x = 11

Question 42.
(a) Prove that \(\frac{\sin x+\sin 3 x+\sin 5 x+\sin 7 x}{\cos x+\cos 3 x+\cos 5 x+\cos 7 x}\) = tan 4x

[OR]

(b) If x + y + z = xyz, then prove that \(\frac { 2x }{ 1-x^{ 2 } } \) + \(\frac { 2y }{ 1-y^{ 2 } } \) + \(\frac { 2z }{ 1-z^{ 2 } } \) = \(\frac { 2x }{ 1-x^{ 2 } } \) \(\frac { 2y }{ 1-y^{ 2 } } \) \(\frac { 2z }{ 1-z^{ 2 } } \)

Question 43.
(a) If the letters of the word GARDEN are permuted in all possible ways and the strings thus formed are arranged in the dictionary order, then and the ranks of the words

1. GARDEN
2. DANGER

[OR]

(b) \(\underset { x\rightarrow a }{ lim } \) \(\frac{\sqrt{x-b}-\sqrt{a-b}}{x^{2}-a^{2}}\) (a>b)

Question 44.
(a) If the binomial coefficients of three consecutive terms in the expansion of (a + x)ⁿ are in the ratio 1 : 7 : 42 then find n?

[OR]

(b) Evalute \(\sqrt { x^{ 2 }+y^{ 2 } } \) = tan^-1(\(\frac{y}{x}\))

Question 45.
Let \(\vec { a } \), \(\vec { b } \), \(\vec { c } \) be three vectors such that |\(\vec { a } \)| = 3, |\(\vec { b } \)| = 4, |\(\vec { c } \)| = 5 and each one of them being perpendicular to the sum of the other two, find |\(\vec { a } \) + \(\vec { b } \) + \(\vec { c } \)|.

[OR]

(b) Evaluate ∫sec³ 2xdx

Question 46.
(a) Find all the equations of the straight lines in the family of the lines y = mx – 3, for which m and the x-coordinate of the point of intersection of the lines with x – y = 6 are integers?

[OR]

(b) There are two identical boxes containing respectively 5 white and 3 red balls, 4 white and 6 red balls. A box is chosen at random and a ball is drawn from it

1. Find the probability that the ball is white
2. If the ball is white, what is the probability that it from the first box?

Question 47 (a).
If A_i B_i, C_i are the cofactors of a_i, b_i, c_i, respectively, i = 1 to 3 in

[OR]

(b) Express the matrix \(\left(\begin{array}{ccc}
3 & 3 & -1 \\
-2 & -2 & 1 \\
-4 & -5 & 2
\end{array}\right)\) as the sum of symmetric martix and a skew-symmetric martix?

Students can download 6th Social Science Term 1 Geography Chapter 2 Land and Oceans Questions and Answers, Notes, Samacheer Kalvi 6th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 6th Social Science Geography Solutions Term 1 Chapter 2 Land and Oceans

Samacheer Kalvi 6th Social Science Land and Oceans Text Book Back Questions and Answers

A. Choose the correct answer

Question 1.
Which of the following is the smallest ocean on Earth?
(a) The Pacific Ocean
(b) The Indian Ocean
(c) The Atlantic Ocean
(d) The Arctic Ocean
Answer:
(d) The Arctic Ocean

Question 2.
The Malacca Strait connects
(a) The Pacific and Atlantic Oceans
(b) The Pacific and Southern Oceans
(c) The Pacific and Indian Oceans
(d) The Pacific and Arctic Oceans
Answer:
(c) The Pacific and Indian Oceans

Question 3.
Which of the following oceans is the busiest ocean?
(a) The Pacific Ocean
(b) The Atlantic Ocean
(c) The Indian Ocean
(d) The Arctic Ocean
Answer:
(b) The Atlantic Ocean

Question 4.
The frozen continent is
(a) North America
(b) Australia
(c) Antarctica
(d) Asia
Answer:
(c) Antarctica

Question 5.
A narrow strip of water that connects two large water bodies?
(a) A Strait
(b) An Isthmus
(c) An Island
(d) A Trench
Answer:

B. Fill in the blanks

1. The world’s largest continent is …………….
2. ……………. is the mineral-rich plateau in India.
3. The largest ocean is …………….
4. Deltas are ……………. order landforms ……………..
5. The Island continent is …………….

Answer:

1. Asia
2. Chotanagpur Plateau
3. The Pacific ocean
4. Third
5. Australia

C. Circle the odd one out

D. Match the following

Answer:
1. – b
2. – a
3. – d
4. – e
5. – c

E. (i) Consider the following statements

1. Plains are formed by rivers.
2. The ‘South Sandwich Trench’ is found in the Indian Ocean.
3. Plateaus have steep slopes.
Choose the correct answer using the codes given below.
(a) 1 and 3
(b) 2 and 3
(c) 1, 2 and 3
(d) 2 only
Answer:
(a) 1 and 3

(ii) Consider the following statements

Statement I : Mountains are second order landforms.
Statement II : The Mariana Trench is the deepest trench in the world.
Which of the statement(s) is/are true?
(a) I is true; II is wrong
(b) I is wrong; II is true
(c) Both the statements are true
(d) Statements I and II are wrong.
Answer:
(c) Both the statements are true

F. Answer in a word

Question 1.
Which is the highest plateau in the world?
Answer:
Tibetan Plateau.

Question 2.
Name a second-order landform.
Answer:
Mountains or Plateaus or Plains

Question 3.
Which ocean is named after a country?
Answer:
Indian Ocean.

Question 4.
Name the island located in the Arabian Sea.
Answer:
Lakshadweep islands

Question 5.
What is the deepest part of the ocean called?
Answer:
Trench

G. Answer in brief

Question 1.
What is a continent?
Answer:
The vast landmasses on Earth are called Continents.

Question 2.
Name the continents which surround the Atlantic Ocean.
Answer:
The Atlantic ocean is bounded by North America and South America in the West, and ( Europe and Africa in the East)

Question 3.
What are the oceans?
Answer:
Oceans are a vast expanse of water.

Question 4.
List out the names of continents according to their size
Answer:
From the largest to the smallest, they are Asia, Africa, North America, South America,  Antarctica, Europe, and Australia.

Question 5.
Name the oceans which surround North America and South America.
Answer:
North America: On the west by the Pacific Ocean, on the east by Atlantic ocean and on the north by Arctic ocean
South America: On the west by the Pacific Ocean, on the east by Atlantic ocean.

H. Distinguish between

Question 1.
A Mountain and a Plateau?
Answer:
Mountains

1. A landform that rises over 600 meters above its surroundings and has steep slopes is called a mountain.
2. Example: Himalayas

Plateaus

1. Plateaus are the elevated portions of the Earth that have flat surfaces bounded by steep slopes. The elevation of plateaus maybe a few hundred metres or several thousand metre.
2. Example: Chotanagpur Plateau

Question 2.
An ocean and a sea
Answer:

Ocean

1. Oceans are a vast expanse of water.
2. Eg. the Pacific Ocean

Sea

1. Seas are water bodies partially or fully enclosed by land.
2. Eg: Bay of Ben, Arabian Sea.

I. Answer the following questions in detail

Question 1.
Mention the classification of landforms.
Answer:
First-order landforms:

1. Continents and oceans are grouped as first-order landforms.
2. The vast landmasses on Earth are called Continents and huge water bodies are called Oceans.
3. There are seven continents in the world. They are Asia, Africa, North America, South America, Antarctica, Europe and Australia.
4. The five oceans are the Pacific, Atlantic, Indian, Southern, and Arctic Oceans.

Second-order landforms:

1. Mountains, Plateaus, and Plains are grouped as second-order landforms.
2. A landform that rises 600 meters above its surroundings and has steep slopes is called a mountain. Example:
3. The Himalayas, the Rocky Mountains, and the Andes.
4. Plateaus are the elevated portions of the Earth that have flat surfaces bounded by steep slopes. Example:
5. Tibetan plateau and Deccan plateau.
6. Plains are flat and relatively low-lying lands. These plains are used extensively for agriculture. Example: Indo – Gangetic plain.

Third-order landforms:

1. Third-order landforms are formed on mountains, plateaus, and plains mainly by erosional and depositional activities of rivers, glaciers, winds, and waves.
2. Example: Valleys, beaches, and sand dunes.

Question 2.
Write a note on plateaus.
Answer:
Ocean:

• An ocean is a vast expanse of water.
• Oceans are very deep.
• Example: The Pacific Ocean

Sea:

• A sea is a water body partially or fully enclosed by land.
• Seas are not so deep as oceans
• Example: The Arabian sea

Question 3.
Plains are highly populated. Give reasons.
Answer:

1. Plains are flat and relatively low-lying lands.
2. Plains are formed by rivers and their tributaries and distributaries.
3. Plains are used extensively for agriculture due to the availability of water and fertile soil.
4. Plains are most suitable for human inhabitation. Hence, they are highly populated.

Question 4.
Give the important features of the Pacific Ocean,
Answer:

1. The Pacific Ocean is the largest and deepest ocean on Earth.
2. It covers about one-third of the Earth’s total area.
3. It is bounded by Asia and Australia in its west and North America and South America in its east.
4. On its apex is the Bering Strait. It connects the Pacific Ocean with the Arctic Ocean.
5. The deepest point Mariana Trench is located in the Pacific Ocean.
6. A chain of volcanoes is located around the Pacific Ocean.

Question 5.
Write above the importance of oceans.
Answer:

1. Oceans are the first order landform.
2. 71% of the earth’s surface is covered with water.
3. Oceans influence man in various ways, from the climate he experiences to the food he eats.
4. Oceans are a major source of salt, valuable minerals, petroleum, pearls, and diamonds.
5. Ocean currents affect the climate of neighbouring areas.
6. Ocean trade plays an important role in the world economy.
7. Ocean currents can be converted into electricity.

J. Picture Study

Question 1.
Name the landform.
Answer:
Sand dune

Question 2.
What order of a landform is this?
Answer:
Third-order landform

Question 3.
By which activity of river is this landform formed?
Answer:
Deposition

K. (i) Activity (Activity to be done by students)

Trip to the nearby area to appreciate the physical features of any kind of landform.
Conduct a quiz on landforms and oceans.

(ii) Activity

Question 1.
Give examples for the following using an Atlas.
Answer:

1. Bay: Hudson Bay, Bay of Bengal, Bay of Biscay
2. Gulf: the Persian Gulf, Gulf of Kutch, Gulf of Mannar
3. Island: Srilanka, Australia, Maldives
4. Straits: Palk strait, Bering strait, Magellan strait

Question 2.
Map reading (with the help of an atlas)
Answer:

1. A sea in the east of India – Bay of Bengal
2. Continents in the west of Atlantic Ocean – North America, South America
3. Continents in the south of Arctic Ocean – Europe, Asia
4. A strait between India and Sri Lanka – Palk strait
5. Oceans which surround Australia – Indian ocean, Pacific ocean
6. Find out the Isthmusses – Isthmus of Panama, Isthmus of Avalon, Isthmus of La Dune

Samacheer Kalvi 6th Social Science Land and Oceans Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
International Mountain Day is ……………..
(a) June 15
(b) April 11
(c) November 11
(d) December 11
Answer:
(d) December 11

Question 2.
Andes mountain is located in
(a) North America
(b) South America
(c) Asia
(d) Europe
Answer:
(b) South Amei leaf

Question 3.
The highest plateau in the world is …………….
(a) Ladakh plateau
(b) Tibetan plateau
(c) Deccan plateau
(d) Chotanagpur plateau
Answer:
(b) Tibetan plateau

Question 4.
The International Mountain Day is
(a) December 10th
(b) December 11th
(c) December 12th
(d) December 13th
Answer:
(b) December 11th

Question 5.
It connects the Pacific Ocean with the Arctic ocean.
(a) Bering strait
(b) Magellan strait
(c) Gibraltar strait
(d) Palk strait
Answer:
(a) Bering strait

II. Fill in the blanks

1. The sea around Pangea is called ……………….
2. The smallest continent is ……………….
3. The smallest ocean is ……………….
4. ………………. is called the Roof of the world
5. The deepest point in the Indian ocean is ……………….

Answer:

1. Panthalasa
2. Australia
3. Arctic ocean
4. Tibetan Plateau
5. Java trench

III. Answer in brief

Question 1.
What is an Isthmus?
Answer:
A narrow strip of land which connects two large landmasses or separates two large water bodies is called an Isthmus.

Question 2.
What are the Second-order landforms?
Answer:
The Second-order landforms are categorised as mountains, plateaus, and plains.

Question 3.
Bring out the importance of mountains.
Answer:

1. Mountains are the source of rivers.
2. They block the moisture-bearing winds and cause rainfall.
3. They provide shelter to flora and fauna.
4. They promote tourism.
5. During summer people go to mountain regions to enjoy the pleasing cool weather.
6. There are a number of hill stations in the mountains.

Question 4.
Mention some of the early civilizations.
Answer:
The Indus valley civilization, the Mesopotamian civilization, The Egyptian civilization, and the Chinese civilization. Where some of the early civilizations?

Question 5.
Write a few lines about The Indian Ocean.
Answer:

1. The Indian Ocean is the third largest ocean on the earth.
2. It is named after India.
3. It is triangular in shape.
4. The Andaman and Nicobar Islands, Lakshadweep, Maldives, Sri Lanka, and Mauritius are the islands located in the Indian Ocean.
5. Java Trench is the deepest point in this ocean.

IV. Mind Map

Students can download 6th Social Science Term 1 History Chapter 4 Ancient Cities of Tamilagam Questions and Answers, Notes, Samacheer Kalvi 6th Social Science Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

Tamilnadu Samacheer Kalvi 6th Social Science History Solutions Term 1 Chapter 4 Ancient Cities of Tamilagam

Samacheer Kalvi 6th Social Science Ancient Cities of Tamilagam Text Book Back Questions and Answers

I. Choose the correct answer

Question 1.
Which of the following region has a city more than 6500 years old?
(a) Iraq
(b) Indus valley
(c) Tamilagam
(d) Thondaimandalam
Answer:
(a) Iraq

Question 2.
Which one of the following is a Tamil city?
(a) Iraq
(b) Harappa
(c) Mohenjo-Daro
(d) Kancheepuram
Answer:
(d) Kancheepuram

Question 3.
Which city is not related to the Bay of Bengal?
(a) Poompuhar
(b) Thondi
(c) Korkai
(d) Kancheepuram
Answer:
(b) Madurai

Question 4.
The water management system of Tamils are known from
a. Kallanai
b. Tanks in Kancheepuram
c. Prakirama Pandyan Tank
d. River Cauvery
(a) (a) is correct
(b) (b) is correct
(c) (c) is correct
(d) (a) and (b) are correct
Answer:
(d) (a) and (b) are correct

Question 5.
Which is not the oldest city among the following ones?
(a) Madurai
(b) Kancheepuram
(c) Poompuhar
(d) Chennai
Answer:
(a) Madurai

Question 6.
Which city is related to Keezhadi excavation?
(a) Madurai
(b) Kancheepuram
(c) Poompuhar
(d) Harappa
Answer:
(a) Madurai

II. Tick the appropriate answer. Match the statement with the reason

Question 1.
Statement: Goods were imported and exported from the city of Poompuhar.
Reason: the Bay of Bengal was suitable for trading with neighbouring countries.
(a) Statement is correct, but the reason is wrong.
(b) Statement and its reason are correct.
(c) Statement is wrong, but the reason is correct.
(d) Both are wrong.
Answer:
(b) Statement and its reason are correct.

Question 2.
(a) Thirunavukkarasar said “kalviyil karaiillatha”. This statement refers to the city of Kancheepuram.
(b) Hieun Tsang said, “Kancheepuram is one among the seven sacred places of  India”.
(c) Kalidasa said, “Kancheepuram is the best city among the cities”
(a) only a is correct (b) the only b is correct
(c) the only c is correct (d) All are correct
Answer:
(d) All are correct!

Question 3.
Find out the correct statement
(a) Naalangadi – Night shop
(b) Allangdi – Day -time shop
(c) Ancient Roman coin factory was found at Poompuhar.
(d) Pearls were exported from Uvari near Korkai.
Answer:
(d) Pearls were exported from Uvari near Korkai

Question 4.
Find out the wrong statement.
(a) Megasthanese has mentioned Madurai in his account.
(b) Hien Tsang came to the Tamil city of Kancheepuram.
(c) Kovalan and Kannagi lived in Kancheepuram.
(d) Iraq is mentioned in Pattinapalai.
Answer:
(c) Kovalan and Kannagi lived in Kancheepuram.

Question 5.
Find out the correct pair
(a) Koodal Nagar – Poompuhar
(b) Thoonga Nagaram – Harappa
(c) City of Education – Madurai
(d) City of Temples – Kancheepuram
Answer:
(d) City of Temples – Kancheepuram

Question 6.
Find out the wrong pair
(a) Vadamalai – Gold
(c) Southern Sea – Pearls
(b) Western Ghats – Sandal
(d) Eastern Sea – Ahil
Answer:
(d) Eastern Sea – Ahil

III. Fill in the blanks

1. Kanchi Kailasanathar temple was built by ……………..
2. …………….. is known as the city of temples.
3. Masathuvan means ……………..

Answer:

1. Raja Simh
2. Kanchi
3. A big trader

IV. State True or False:

1. Cultural relationship with the outside world developed in Poompuhar because of its trade relationship with it.
2. Women also purchased from Allangadi of Madurai without fear.
3. Many rock-cut temples were made during the Pallava period.
4. Bodhi Dharma belonged to Kancheepuram.

Answer:

1. True
2. True
3. False
4. True

V. Answer in one word

Question 1.
What do you know about the term ‘export’?
Answer:
Exports are goods and services produced in one country and purchased by the citizens of another country.

Question 2.
Mention the epic and the Sangam poem you read in this lesson.
Answer:

1. The epic is Silapthikaram (or) Manimegalai.
2. Sangam Literature is Pattinappaalai.

Question 3.
Which is the oldest city in Thondai Nadu?
Answer:
Kanchi is the oldest city in Thondai Nadu.

Question 4.
Point out anyone difference between a village and a city.
Answer:
A village will have a small group of settlements whereas a city will have a large group of settlements.

Question 5.
Which civilization is associated with the city Lothal?
Answer:
The Indus Valley Civilisation is associated with the city Lothal.

Question 6.
Name the oldest civilization of the world
Answer:
Mesopotamian civilization is the earliest civilization in the world.

VI. Answer the following

Question 1.
Write a brief note on ancient cities in India?
Answer:

1. Harappa and Mohenjodaro were prominent cities of ancient India.
2. They developed along the banks of the river Indus.
3. They were the symbol of urban civilization.
4. They had very good town planning, a well-constructed house, well-maintained drainage system.
5. They had very good civic sense.
6. They developed pottery, ornaments as well as a script which is yet to be deciphered.

Question 2.
Mention the ancient cities of Tamil Nadu.
Answer:

1. In Tamizhagam the well-known cities were Madurai, Kanchi, and Poompuhar.
2. Poompuhar is one of the oldest towns in ancient Tamizhagam.
3. Madurai has been one of the oldest cities in India.
4. It is known as “Sangam Valartha Nagaram”
5. Kanchi is the oldest town in Thondai Nadu.
6. Scholars like Dharmabalar, Jothibalar, Sumathi, and Bodhi Dharma were born in Kanchi.

Question 3.
Discuss the sources available to know about Tamil cities?
Answer:

1. Tamil literature, accounts of foreign travellers, and archaeological finds provide information about the ancient towns of Tamizhagam.
2. Sangam Tamil Literature Pattinappaalai and Tamil epics Silappathikaram and Manimegalai have references about Poompuhar.
3. Madurai is proudly associated with three Sangams.
4. The fame of Madurai can be attested from the accounts of the Greek historian Megasthenes.
5. Chanakya mentions Madurai in his famous work Arthashastra.
6. The Chinese Traveller Hieun Tsang writes about the greatness of Kanchi.
7. Poet Kalidasa refers to Kanchi as the best of the towns.

Question 4.
Write about the kings who ruled Madurai.

1. Pandyas, the Cholas and later the Kalabras ruled Madurai in the ancient
2. During medieval times, later Cholas and later Pandyas followed by the Nayaks ruled this historic town.

Question 5.
Mention the other names of Madurai?
Answer:

1. Sangam Valartha Nagaram
2. Thoonga Nagaram (the city that never sleeps).
3. Koodal Nagar are the other names of Madurai

Question 6.
What is the difference between Naalaugadi and Allangadi?
Answer:
Naalangadi

1. It is Day Marget.
2. It works only in the day time.

Allangadi

1. It is the evening Market.
2. It works only in the Evening,

Question 7.
Name the scholars who were born at Kancheepuram
Answer:
Scholars like Dharmabalar, Jothibalar, Sumathi, and Bodhi Dharma were bom in Kanchi.

Question 8.
Which is known as the city of lakes? Why?
Answer:

1. Water management played an important role in the agrarian society of those times.
2. Hundreds of lakes were created for storing water around the town of Kanchi.
3. These lakes were well connected with canals.
4. During the later period, Kanchi came to be known as the district of lakes.

VII. HOTS

Question 1.
Write a short note on Iraq.
Answer:

1. Modem Iraq was called Mesopotamia in the ancient period. It was the birthplace of Sumerian civilization.
2. Iraq is watered by two rivers namely Euphrates and Tigris.
3. It is an important trading centre.
4. Pattinappaalai speaks about the trade relations of Iraq With other countries.

Question 2.
Write a paragraph about the city of Poompuhar with special reference to trade.
Answer:

1. Poompuhar was a port.
2. Big traders and sea traders had settled down there.
3. Numerous merchants from foreign countries such as Greece and Rome landed at Poompuhar.
4. Brisk seaborne trade took place in Puhar.
5. Foreign traders stayed on indefinitely at Puhar.
6. There is evidence of foreign settlements in the town.

Question 3.
Write about the accounts given by scholars about Kanchi.
Answer:

1. Poet Kalidasa says “Kanchi is the best of the towns”.
2. Poet Thirunavukarasar praises Kanchi as “Kalviyil Karaiillatha Kanchi.
3. Hieun Tsang has said,”Kanchi can be counted as one among the seven sacred places like Budh Gaya and Sanchi”.

Question 4.
City of temple Gives short notes.
Answer:

1. Kanchi is also known as the Temple city.
2. The famous Kailasanathar temple is at Kanchi.
3. There are a large number of cave temples in Kanchi. So Kanchi is known as the Temple city.

Question 5.
Kancheepuram was famous for education. Prove this statement
Answer:

1. Several schools were established in great numbers in Kanchi.
2. There were Jainpallis and Viharas.
3. The Chinese traveller Hieun Tsang visited Kanchi Kadigai to continue his studies
4. Tamil poet saint Thirunavukarasar praises Kanchi as’Kalviyil karaiillatha Kanchi’.

VIII. Student Activity

1. Make an album about Keezhadi excavations.
2. Poompuhar was famous for trading activities. Discuss.
3. Collect the pictures of Pallava temple architecture.
4. Prepare a Booklet describing the famous lakes of Tamilnadu.
5. Make a booklet about the famous cities of Tamilnadu.
6. Go to the library and find out the places of importance in your district.

IX. Answer Grid

Question 1.
Poompuhar was located on which riverbank?
Answer:
Cauvery

Question 2.
Name the ancient city which had Tamil Sangam.
Answer:
Madurai

Question 3.
Name a Sangam literary work.
Answer:
Pattinappaalai

Question 4.
Which Greek historian gave accounts about the Pandya kingdom?
Answer:
Megasthanese

Question 5.
To which the Tamil Kingdom did the southern districts of Tamil Nadu belong to during the Sangam Age?
Answer:
Pandyas.

Question 6.
Name the Chinese traveller who stayed and studied in Nalanda University.
Answer:
Hieun Tsang

Question 7.
Thirunavukarasar mentioned Kanchi as _______
Answer:
Kalviyil karaiillatha Kanchi

Question 8.
What is the name of the evening market during the Sangam Age?
Answer:
Allangadi

Question 9.
Name the temple built by Pallava king Rajasimha at Kanchi.
Answer:

1. Kailasanathar
2. Temple.

Question 10.
Which district is known as the district of lakes?
Answer:
Kanchi

Question 11.
What is trade?
Answer:
The act of buying and selling goods and services is called trade.

Question 12.
Name a port located on the shore of the Bay of Bengal
Answer:
Chennai.

X. Life Skill (For Students)

1. Make a handout that shows the importance of the place where you live.

Samacheer Kalvi 6th Social Science Ancient Cities of Tamilagam Additional Important Questions and Answers

I. Choose the correct answer

Question 1.
The earliest civilization in the world is …………….
(a) Egyptian Civilization
(b) Chinese civilization
(c) Indus valley civilization
(d) Mesopotamian civilization
Answer:
(d) Mesopotamian civilization

Question 2.
Name the place related to the export of Sandal.
(a) the Western Ghats
(b) Southern Sea
(c) Eastern Sea
(d) Elam
Answer:
(a) the Western Ghats

Question 3.
Kailasanathar temple was built by …………….
(a) Mahendra varman
(b) Narasimha Varman
(c) Raja Simha
(d) Aparajitha
Answer:
(c) Raja Simha

Question 4.
Ahil was a
(a) Port
(b) Fragrant wood
(c) Educated centre
(d) Ornament
Answer:
(b) Fragrant wood

Question 5.
Puhar served as the port of ……………
(a) Chera kingdom
(b) Chola kingdom
(c) Pandya kingdom
(d) Kalabras
Answer:
(b) Chola kingdom

II. Fill in the blanks

1. Sea traders are known by the name ……………
2. Chanakya was Chandragupta’s ……………
3. The Buddhist monk Manimegalai spent the last part of her life at ……………

Answer:

1. Maanaigan
2. Minister
3. Kanchi

III. State True or False

1. The lead female character of Silappathikaram is Manimegalai
2. The present-day Thanjavur was once part of Chera Nadu
3. Poompuhar served as the port of the early Chola kingdom
4. Silappathikaram speaks about the greatness of Poompuhar
5. Many cave temples were built during the Pallava period

Answer:

1. False
2. False
3. True
4. True
5. True

IV. Answer the following

Question 1.
How was Poompuhar different from other towns?
Answer:
Each social group had a separate settlement
Streets were broad and straight, dotted with well-designed houses.
There was also a dockyard

V. Mind map