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Tamilnadu State Board New Syllabus Samacheer Kalvi 12th English Guide Pdf Poem 2 Our Casuarina Tree Text Book Back Questions and Answers, Summary, Notes.

Tamilnadu Samacheer Kalvi 12th English Solutions Poem 2 Our Casuarina Tree

12th English Guide Our Casuarina Tree Text Book Back Questions and Answers

Textual Questions:

1. Fill in the blanks choosing the words from the box given and complete the summary of the poem:
(Text Book Page No. 54)

Question 1.
The casuarina tree is tall and strong, with a creeper winding around it like a (1)_______. The tree stands like a (2) ________ with a colourful scarf of flowers. Birds surround the garden and the sweet song of the birds is heard. The poet is delighted to see the casuarina tree through her (3)_______. She sees a grey monkey sitting like a (4) ________ on top of the tree, the cows grazing, and the water lilies (5) ________ in the pond. The poet feels that the tree is dear to her not for its (6) appearance but for the (7) _______ memories of her happy childhood that it brings to her. She strongly believes that (8) _________ communicates with human beings. The poet could communicate with the tree even when she was in a far-off land as she could hear the tree (9) ________ her absence. The poet (10) ________ the tree’s memory to her loved ones, who are not alive. She immortalizes the tree through her poem like the poet Wordsworth who (11)________ the yew tree of Borrowdale in verse. She expresses her wish that the tree should be remembered out of love and not just because it cannot be (12)_______.

Answer:

1. python
2. giant
3. casement
4. statue
5. springing
6. impressive
7. nostalgic
8. nature
9. lamenting
10. consecrates
11. sanctified
12. forgotten

2. Based on your understanding of the poem, answer the following question in one or two sentences each:
(Text Book Page No. 55)

Question a)
What is the creeper compared to? Which tree is referred to here?
Answer:
The creeper is compared to a lady’s love.

Question b)
How does the creeper appear on the tree? Who is the giant here?
Answer:
The creepers appear like a rugged trunk with deep scars. The tree is the giant here.

Question c)
Describe the garden during the night.
Answer:
At night, the garden overflows with an endless melodious song sung by the dark king from the Casuarina Tree when the men are sleeping.

Question d)
How does the poet spend her winter?
Answer:
The poet spends her winter by seeing a gray monkey sitting like a statue on top of the tree and watching the activities of the younger monkey on the tree.

Question e)
Name the bird that sings in the poet’s garden?
Answer:
Nightingale sings in the poet’s garden.

Question f)
Why is the Casuarina tree dear to the poet’s heart?
Answer:
The poet feels that the tree is dear to her not for its impressive appearance but for the nostalgic memories of her happy childhood that it brings.

Question g)
Does nature communicate with human beings?
Answer:
Yes, nature communicates with human beings. William Wordsworth is a strong advocate of this communication.

Question h)
What has Wordsworth sanctified in his poem?
Answer:
The poet Wordsworth has sanctified the yew tree of Borrowdale in verse.

Question i)
To whom does Toru Dutt want to consecrate the tree’s memory?
Answer:
Torn Dutt wants to consecrate the memories of the tree to her loved ones.

Question j)
The casuarina tree will be remembered forever why?
Answer:
Because of the poet’s love for the tree.

3. Read the lines given below and answer the questions that follow: (Text Book Page No. 55)

“A creeper climbs, in whose embraces bound
No other tree could live”.

i) Which tree is referred to in the above lines?
Answer:
Casuarina tree is referred to in the above line.

ii) How does the tree survive the tight hold of the creeper?
Answer:
The tree is so strong that it bears the tight hold of the creeper.

iii) Why does Toru Dutt use the expression ‘a creeper climbs’?
Answer:
A creeper cannot grow without the support of another tree or a pole. While climbing, it tries to sap the energy from the living tree. If the creeper doesn’t climb, it would die without sunlight. So, the poet says the creeper climbs. It twines its body around the tree and keeps climbing.

b) The giant wears the scarf, and flowers are hung to her.
In crimson clusters all the bough among!

i) Who is the giant here?
Answer:
Casuarina tree’ is the giant here.

ii) Why is the scarf colourful?
Answer:
The crimson flowers are bright and colourful in the tree. So the scarf (crimson flower around the tree seems like a scarf) is colourful.

“Fear, trembling Hope, and Death, the Skeleton,
And time the shadow”, and though weak the
verse
That would thy beauty fain, oh, fain rehearse
May love to defend thee from oblivion’s curse.

i) What does the poet mean by the expression ‘May love defend thee from oblivion’s curse’?
Answer:
It means that the tree should be remembered out of love and not just because it cannot be forgotten.

ii) What does the expression ‘fain’ convey?
Answer:
The expression ‘fain’ means eagerness. Here, the poet is very happy and proud to remember the tree which is very dose to her heart.

iii) What does the poet convey through the expression ‘fear, trembling hope’?
Answer:
The poet conveys the deep feeling of her love towards the tree through the expression ‘fear, trembling hope’. The poet hopes that the tree will be remembered forever as the yew trees of Borrowdale immortalized by Wordsworth are still remembered.

Additional Questions:

a) “And oft at nights the garden overflows
with one sweet song that seems to have no close,
Sung darkling from our tree, while men repose”.

i) Hoe does the garden overflow?
Answer:
The garden overflows with sweet songs of the bird from the tree.

ii) When do the birds sing?
Answer:
The birds sing at night while men are taking rest.

b. “When first my casement is wide open thrown
At dawn, My eyes delighted on it rest?

i) What does ‘casement’ mean?
Answer:
Casement means window.

ii) What brings her delight?
Answer:
By seeing the sight of the Casuarina tree, She feels happy and her heart fulfilled. That tree brings her delight.

c. Sometimes and most in winter – on its crest
A gray baboon sits statue-like alone”

i) Who is sitting like a statue?/Where is the baboon sitting?
Answer:
A gray baboon is sitting like a statue. The baboon is sitting on the Casuarina tree.

ii) When does it come to the tree?
Answer:
During winter it comes to the tree.

d. “But not because of its magnificence
Dear is the Casuarinas to my soul
Beneath it, we have played, though the year may roll”,

i) How does the poet hold the Casuarina tree?
Answer:
The poet holds the Casuarina tree so dear, which brings her sweet memories.

ii) Who do ‘we’ refer to?
Answer:
‘We’ refer to the poet Torn Dutt and her siblings and friends.

e. “Unknown, yet well known to the eye of faith!
Ah, I have heard that wail far, far away”

i) Can the poet communicate with the tree?
Answer:
Yes, the poet can communicate with the tree even when she is in a far off land.

4. Explain the following lines with reference to the context:(Text Book Page No. 56)

a) “Dear is the Casuarina to my soul”

Reference :
This line is taken from Poem – “Our Casuarina tree” Poet – “Torn Dutt”
Context:
The poet expresses her great love for the tree.
Explanation:
The poet feels that the tree is dear to her not for its impressive appearance but for the nostalgic memories of her happy childhood that it brings to her

b) It is the tree’s lament, an eerie speech.

Reference:
This line is taken from the Poem – “Our Casuarina Tree”, Poet – “Toru Dutt”
Context:
The poet brings out the great love of trees towards the poet.
Explanation:
The poet could communicate with the tree even when she was in a far off land. She could hear the tree lamenting her absence as there was a strong bond between her and the tree.

c) “Unto thy honor, Tree, beloved of those
who now in blessed sleep for eye repose,”

Reference:
This line is taken from the Poem – “Our Casuarina Tree”, Poet – “Toru Dutt”.
Context:
The poet brings out her honour and respect towards the tree
Explanation:
The poet consecrates the tree’s memory to her loved ones, who are not alive. She honors it with full of love and affection that shows how much the tree is beloved to her.

6. Answer each of the following questions in a paragraph of 100-150 words: (Text Book Page No. 56)

a) Describe the reminiscences of the poet, when she sees the Casuarina tree.
b) How does nature communicate with the poet?
c) The poet immortalizes the tree. Elucidate

Introduction:
The poem is an attempt by the poet to recapture her past and immortalize it.

Appearance and Comparison of the tree:
The tree is presented both as a symbol and as an object of nature where the poet project both time and eternity. The poem is filled with memories of the past and happy childhood days. She remembers her companions how much she loved them and was loved in return. The giant creeper is compared with a huge python. Water lilies are compared with enmassed snow. She loved the tree very much that’s why she noticed everything keenly and carefully.

Lasting impression:
The Poet describes the lasting impression that the tree has left on her mind. She describes the baboon sitting like a statue on the top of the tree while its young ones play on the lower branches. She also describes the sleepy cows moving slowly to their pastures.

Remembrance of the poet:
She links up the tree with the memories of her dead brother, Abju, and her sister, Aru. She feels great pain when she remembers the happy time that she had with them. The Casuarina tree connects her past with her present.

Communication with the tree:
The poet could communicate with the tree even when she was in a far off land as she could hear the tree lamenting her absence. The poet immortalizes the tree through her poem like poet Wordsworth who sanctified the yew tree of Borrowdale in verse.

Conclusion:
She expresses her wish that the tree should be remembered out of love and not just because it cannot be forgotten. Thus it holds a special place in the poetess’ heart.

Listening:

First, read the questions given below, then listen to the poem, read aloud by the teacher, or played on an audio player. Then answer the questions based on your listening of the poem:

Question 1.
The poet was tossing in the bed awake because of ______.
a) he was worried
b) he was struggling to sleep
C) it was day time
d) he was tired
Answer:
b) he was struggling to sleep

Question 2.
The ______ were ‘sparkling as pearls’.
a) moon
b) sun
c) stars
d) meteoroids
Answer:
c) stars

Question 3.
The ______ gave the poet a motherly smile.
a) sun
b) stars
c) moon
d) sky
Answer:
c) moon

Question 4.
________ made the poet’s eyelids droop.
a) nature
b) rosy lips
c) songs
d) tiredness
Answer:
a) nature

Question 5.
_________ is the title of the poem.
a) Wonders
b) Midnight Wonders
c) Nature
d) Midnight dreams
Answer:
b) Midnight Wonders

நமது சவுக்கு மரம்:

கவிஞரைப் பற்றி டோரு டட் (1856-77) ஒரு வங்காளக் கவிஞர். இந்திய துணைக் கண்டத்தைச் சார்ந்த இவர் ஆங்கிலம் மற்றும் பிரெஞ்சு மொழி எழுத்தாளரும் கூட. இவர் அவரது பெற்றோருக்கு மூன்றாவது பெண் குழந்தை. இவரது குடும்பத்தினர் அனைவரும் கல்வியில் சிறந்தவர்களாகவும், புலவர்களாகவும் உள்ளனர். இவளுக்கு ஆங்கிலம் கற்றுத்தர சிறந்த ஆசிரியர்கள் வீட்டிற்கே வரவழைக்கப்பட்டனர். பின் இவளுக்கு ஐரோப்பாவிலும், இங்கிலாந்திலும் நீண்ட நாட்கள் வாழ வாய்ப்பு கிடைத்தது.

இவ்வாறு மேற்கத்திய வாழ்க்கையிலும் கலாச்சாரத்திலும் இருந்தாலும் அவர் ஒரு இந்தியர் என்ற உணர்வு மாறாமல் இருந்தார். “பழம்பெரும் பாடல்கள்” மற்றும் “தலைசிறந்த இந்துஸ்தானியர்” போன்ற பிரபல பாடல்தொகுப்புகளோட “Sheaf Gleaned in French Fields” என்ற தலைப்பில் பிரெஞ்சுக் கவிதைத் தொகுப்பினையும் எழுதியுள்ளார். இவரது கவிதைகளிலேயே சிறந்த எங்கள் சவுக்கு மரம் என்ற இந்த பாடல் இவரது மேலும் பல பாடல்கள் என்ற தொகுப்பில் இடம்பெற்றுள்ளது.

கவிதையைப் பற்றி:

கவிஞர் தன் வீட்டின் முற்றத்தில் வளர்ந்திருக்கும் சவுக்கு மரத்தை பற்றியும் அதன் உருவமைப்பு, வளர்ந்திருக்கும் விதத்தைப் பற்றியும் இந்த கவிதையில் அழகாய் வர்ணிக்கிறார். சவுக்கு மரத்திற்கும் தனக்கும் உள்ள அன்பு பிணைப்பை எடுத்துரைப்பதோடு, அதை பார்க்கும்போதெல்லாம் தன் கடந்த கால குழந்தைப் பருவத்தை நினைவிற்கு கொண்டுவந்ததை நமக்கு இக்கவிதை வழியாக எடுத்துரைக்கிறார்.

அவர் அவ்விடத்தில் இல்லாமல் போனதற்காக அம்மரம் புலம்புவதை அவரால் கேட்க முடிகிறது. அவரின் (மூதாதையரின் நினைவாக அந்த மரத்திற்கு உயிர் கொடுத்து அதை அதிகமாக நேசிக்கிறார். அதைப்பற்றி விரிவாக கீழே காண்போம்.

Our Casuarina Tree Summary in Tamil

தமிழாக்கம் மிகப்பெரிய தழும்புகள் நிறைந்த
முரட்டு உடல் படைத்த மலைப்பாம்பு (சவுக்கு மரம்) ஒன்று சுருண்டு கிடப்பது போல்
விண்மீன்களுடன் சந்திப்பு நிகழ்த்தப்போவது போல்,
ஒரு கொடி ஏறுகின்றது, அதன் தழுவல் பிணைப்பில்
வேறெந்த மரமும் வாழ இயலாது.

ஆனால் கம்பீரமாக அந்த ராட்சசன் (the giant) தாவணி அணிந்திருக்க,
செந்நிற மலர்கள் அம்மரத்தின் கிளையெங்கும் கொத்துக்களாய் பூத்துக் குலுங்க,
அந்நேரம் பறவைகளும் தேனீக்களும் அவற்றை மொய்க்க,
அடிக்கடி இரவில் அந்த தோட்டத்தில் ஓர் இனிய பாடல் நெருக்கமின்றி,
அம்மரத்திலிருந்து மக்கள் உறங்கும்போது பாடப்பட்டது.

மாலை மங்கும் போது எனது பை திறந்த நிலையில் எறியப்பட்டிருப்பதை
முதலில் பார்த்த போது எம்மனதில் மகிழ்ச்சி, சிலசமயம், மழைக்காலத்தில்,
அதன் முகட்டின் மேல் ஒரு சாம்பல் நிறக்குரங்கு சிலைபோல்
தனியே அமர்ந்து சூரிய உதயம் காண,
கீழ் கிளையில் அக்குரங்கின் இளவல் தாவிக் குதித்து விளையாடுகிறது.

அருகிலும் தொலைவிலும் சிட்டுக் குருவிகள் புகழ் பாட
அதன் புல்வெளிகளுக்கு நமது பசுக்கள் படையெடுக்க
அம்மர நிழல் அருகிருந்த பெரிய தண்ணீ ர் தொட்டியில் படர
அவ்வளவு அழகாக அவ்வளவு பெரிதாக – நீர்
அல்லிப் பூக்கள் மலர்ந்து குவிந்திருக்கிறது பனிபோல்.

ஆனால் இம்மரத்தின் மீதான எனது அன்பு
அதன் பிரம்மாண்ட தோற்றத்தினால் அல்ல,
அதனடியில் நாங்கள் விளையாடியிருக்கிறோம்.
வருடங்கள் உருண்டாலும் இனிய உறவுகளே, ஆழமான அன்போடு நேசித்தவர்களே,
உங்களால் தான் இம்மரம் எனது நெருக்கமானது.
உங்கள் உருவங்கள் கலந்து இது மேலெழட்டும் நினைவில்,
கதகதப்பான கண்ணீர் என் கண்களை மறைக்கும் வரை!
இறுதியஞ்சலி போல் என் காதினில் ஒலிப்பது என்னவோ
பாறை நிறை கடற்கரையில் உடையும் கடல் போல்?
இது அம்மரத்தின் ஓலம், ஓர் விந்தை பேச்சு,
ஒருவேளை யாரும் அறியா தீவினை சென்றடைவதற்கோ?

யாருமறியாதது இருந்தும் நம்பிக்கையின் கண்கள் நன்கறிந்தது.
ஆ! நான் அந்த புலம்பலை தொலைவினின்று கேட்டிருக்கிறேன்.
தூரத்து நாடுகளில், பிரான்ஸிலும் இத்தாலியிலும் கடற்கரை ஓரங்களை
நெருங்கும் போதெல்லாம் கேட்டிருக்கிறேன்.
நிலவொளியில் நான் நடந்து செல்லும்போது கேட்டிருக்கிறேன்.
நிலமகள் மயங்கும் வேளையிலும் கேட்டிருக்கிறேன்.
ஒவ்வொரு முறை இந்த பாடல் கேட்கும் போதும் ஓயாமல் நினைவூட்டுகிறது
ஒரு பிரம்மாண்ட உருவத்தை உன் உருவமே,
ஓ மரமே! என் மகிழ்ச்சி தருணத்தில் உன்னைக் காண்கிறேன்,
எனது அன்பு காலநிலையில் என் உள்ளம் காண்பது உன் உருவமே.

ஆகவே நான் ஆர்வமாய் உனக்கொரு சிலை நிறுவுவேன்.
உனது மகிமைக்காக, மரமே! என் உயிருக்கும் மேலான என் அன்புக்குரியவர்கள்
நித்திய இளைப்பாறுதல் பெற்றவர்கள்.
அவர்களது அன்பிற்கும் பாத்திரமான உனக்காக!
பாரோடேலில் (Borrowdale) உள்ள அழிவற்ற மரங்களோடு சேர்த்து நீயும் எண்ணப்படுவாயாக,
என் காலம் முடிந்த பின்னும் உன் வலுவிழந்த கிளையடியில் உலாவுகிறது என் மனது,
“பயம், நடுங்கும் நம்பிக்கை மற்றும் இறப்பு, எலும்புக்கூடு நேர நிழல்,
வலுவற்ற வார்த்தைகளாய் இருந்தாலும் அதுவே அழகானது,
அழகான பாடலானது மறதியின் சாபத்திலிருந்து காக்கப்படும் என் அன்பு”.

Tamilnadu State Board New Syllabus Samacheer Kalvi 4th English Guide Pdf Term 3 Poem 2 The Painter Text Book Back Questions and Answers, Summary, Notes.

Tamilnadu Samacheer Kalvi 4th English Solutions Term 3 Poem 2 The Painter

4th English Guide The Painter Book Back Questions and Answers

A. Name the pictures and match it with the rhyming words.

Question 1.
_________  will
Answer:
Hill

Question 2.
________  rush
Answer:
Brush

Question 3.
________  floor
Answer:
Shore

Question 4.
________  dancer
Answer:
Panther

B. Answer the following questions.

Question 1.
What does she paint?
Answer:
She paints valley and hill.

Question 2.
Does the brush bend to her will?
Answer:
Yes, her brush bends to her will.

Question 3.
How does she move the brush?
Answer:
She moves the brush like a dancer.

I. Answer the following Additional Questions and Answers.

Question 1.
Where does the painter sit while painting?
Answer:
The painter was sitting on the cold mud floor while she was painting.

Question 2.
How does she paint on the canvas?
Answer:
She painted on the canvas by holding the brush in her toes on the leg and moving it gently.

Question 3.
What does she draw?
Answer:
She draws a big black panther.

A) Match the adjective with the appropriate picture.

Question 1.

Answer:
Spicy

Question 2.

Answer:
Fast

Question 3.

Answer:
shady

Question 4.

Answer:
sweet

Question 5.

Answer:
Brave

Question 6.

Answer:
Long

B. Use the picture and the words to write the adjective.

Question 1.
The giraffe is ________.
Answer:
Tall

Question 2.
Its neck is ________.
Answer:
Long

Question 3.
Its eyes are ________.
Answer:
Round

Question 4.
Its skin is ________.
Answer:
Yellow

Question 5.
Its tail is ________.
Answer:
Short

Question 1.
There are ________ birds.
Answer:
Three

Question 2.
The birds feather is very ________.
Answer:
Soft.

Question 3.
The colour of the birds is _________.
Answer:
Blue

Question 4.
It is __________ in size.
Answer:
Small

Question 5.
The babies are ___________.
Answer:
Hungry

C. Use adjectives you think for each of these words. You can write more than one adjectives.

Question 1.
A __________ boy.
Answer:

1. A Clever boy
2. A good boy
3. A fat boy
4. A tall boy

Question 2.
A __________ wind.
Answer:

1. A stormy wind
2. A dusty wind

Question 3.
A ___________ flower.
Answer:

1. A beautiful flower
2. A lovely flower

Question 4.
A __________ friend.
Answer:
A good friend

Question 5.
A ___________ sun.
Answer:

1. A hot sun
2. A bright sun

D. Match each sentence to the correct picture by writing the number in the box.

Question 1.

Answer:

1. A brown and white puppy is having fun.
2. Wild animals are in the thick forest.
3. A cute boy is painting with green colour.
4. A naughty boy is riding horse with his sleepy dog.

Let us speak

Phrases in a dialogue

Question 1.
Borrowing a book from public library.
Answer:

Librarian : How can I help you?
Myself : I couldn’t find the book I was looking for.
Librarian : Did you search the correct shelf?
Myself : Yes. It should have been there, but it isn’t.
Librarian : Someone may have taken it.
Myself : Will you be getting another copy anytime soon?
Librarian : I’m sure we will.
Myself : Would you be able to reserve it for me?
Librarian : I will reserve it.
Myself : Thank you very much.

Phrases in a dialogue Additional Questions and Answers.

Question 1.
Going to a textile shop to buy a dress.
Answer:
Shop keeper : Welcome to our shop.
Myself : I want to buy a dress for myself. Can you help me?
Shop keeper : Sure sir. Do you look for formal wear?
Myself  : Yes sir.
Shop keeper : Can you look in the shelf opposite?
Myself : Thank you! But these cost above my budget.
Shop keeper : Please choose sir; we will offer a discount.
Myself : OK then it is fine.
Shop keeper : You have chosen a good one sir. Shall I make the bill?
Myself : Please do.

Additional Questions

More Adjectives

Underline the adjectives in the sentences and substitute it with another suitable adjective.

Question 1.
His shirt is _________ in colour.
Answer:
Yellow
(Another adjective) – Green

Question 2.
My pillow is ___________ in shape.
Answer:
Round
(Another adjective) – Rectangle

Question 3.
She lives in a __________ house.
Answer:
Big
(Another adjective) – Small

Question 4.
There are __________ birds on the branch.
Answer:
Two
(Another adjective) – Five

Question 5.
She has a __________ complexion.
Answer:
Black
(Another adjective) – Wheatish

Question 6.
The hall is __________ in shape.
Answer:
Rectangle
(Another adjective) – Square

Question 7.
The building occupies a ___________ area of land.
Answer:
Huge
(Another adjective) – Vast

Question 8.
I am __________ years old.
Answer:
ten
(Another adjective) – Nine

Let us listen

Listen to the audio and tick (✓) true or false.

Question 1.
It is a breakable pencil.
Answer:
False

Question 2.
It has double spring mechanism.
Answer:
True

Question 3.
It absorbs the pressure.
Answer:
True

Question 4.
You can’t hold the pencil hard.
Answer:
False

Question 5.
It gives confident and peace of mind.
Answer:
True

The Painter Summary in English and Tamil

Sitting on the cold mud floor,
She paints the valley and hill,
Giving life to the canvas shore,
Sees the brush bend to her will.
Her canvas used to be colourless,
Until she learnt that her brush’s strokes,
Are not always aimless,
The flow of paint never chokes!
She dips her brush,
To draw the big black panther,
Her legs never in a rush,
She moves them like a dancer!

ஈரமான மண் தரையில் அமர்ந்து
அவள் பள்ளத்தாக்கையும், மலையையும் வரைகிறாள்.
ஓவிய துணிக்கு உயிர் கொடுத்தபடி
தூரிகை அவள் விருப்பத்திற்கேற்ப வளைவதைப் பார்க்கிறாள்.!
அவளுடைய ஓவியத்துணி நிறமற்று இருந்தது
அவளது தூரிகை அசைந்து, அசைந்து வண்ண ம்தீட்டுவதை அவள் அறியும் வரை!
அவை எப்போதும் இலக்கு அற்றதாக இருந்ததில்லை
வண்ண வீச்சு ஒருபோதும் தடைப்பட்டதில்லை!
அவள் தூரிகையைத் தோய்க்கிறாள்,
பெரிய கறுப்பு சிறுத்தையை வரைவதற்காக
அவள் கால்கள் எப்போதும் அவசரப்படவில்லை ,
அவள் அவற்றை (கால்களை) ஒரு நடனக்காரியை போல நகர்த்துகிறாள்!

The Painter Glossary

Bend – shape into a curve (வளைவாக வடிவம் அடைதல்)
Bend to her will – moves to her directions (அவள் விரும்பியபடி நகர்தல்)
Chokes – stops (தடைப்படுத்துதல்)
Giving life – making realistic (ஓவியத்திற்கு உயிரூட்டுதல்)
Colourless – without any drawing on it (ஓவியம் வரையப்படாமல்) நிறமற்ற நிலை)
Dip – put something in liquid (ஒரு (வண்ண ) திரவத்தில் எதையாவது தோய்த்தல்)
Never in a rush – always did not hurry (ஒருபோதும் அவசரப்படவில்லை)
Strokes – gentle movement of hand (மென்மையான அசைவுகளுடன் வரைதல்)

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 3 Trigonometry Ex 3.1 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Maths Solutions Chapter 3 Trigonometry Ex 3.1

Question 1.
Identify the quadrant in which an angle of each given measure lies,
(i) 25°
(ii) 825°
(iii) – 55°
(iv) 328°
(v) – 230°
Answer:
(i) 25°

25° First quadrant

(ii) 825°

825° = 9 × 90° + 15°
825° = 2 × 360° + 105°
∴ 825° lies in the second quadrant.

iii) -55°

-55° lies in the fourth quadrant

iv) 328°

328° = 270° + 58° lies in the fourth quadrant.

v) -230°

– 230° = – 180° + (- 50°) lies in the second quadrant.

Question 2.
For each given angle, find a co-terminal angle with a measure of 9 such that 0 ≤ θ < 360°.
(i) 395°
(ii) 525°
(iii) 1150°
(iv) – 270°
(v) – 450°
Answer:
(i) 395°
395° = 360° + 35°
395° – 35° = 360°
∴ Coterminal angle for 395° is 35°

(ii) 525°
525° = 360° + 165°
360° – 165° = 360°
∴Coterminal angle for 525° is 165°

(iii) 1150°
1150° = 360° + 360° + 360° + 70°
1150° = 3 × 360° + 70°
1150° – 70° = 3 × 360°
∴ Coterminal angle for 1150° is 70°.

(iv) – 270°
– 270° = 360° + 90°
– 270° – 90° = 360°
∴ Coterminal angle for -270° is 90°

(v) – 450°
– 450° = – 720° + 270°
– 450° – 270° = – 2 × 360°
∴ Coterminal angle for – 450° is 270°

Question 3.
If a cos θ – b sin θ = c , show that a sin θ + b cos θ = ± \(\sqrt{\mathbf{a}^{2}+\mathbf{b}^{2}-\mathbf{c}^{2}}\)
Answer:
a cos θ – b sin θ = c
(a cos θ – b sin θ)² + (a sin θ + b cos θ)² = a² cos² θ – 2 ab sin θ cos θ + b² sin²θ + a² sin² θ + b² cos² θ + 2 ab sin θ cos θ
c² + (a sin 0 + b cos θ )² = a² cos² θ + a² sin² θ + b² sin² θ + b²cos²θ
= a² (cos²θ + sin²θ) + b²(sin²θ + cos²θ)
c² + (a sin θ + b cos θ )2 = a² + b²
(a sin θ + b cos θ)² = a² + b² – c²
a sin θ + b cos θ = ± \(\sqrt{\mathbf{a}^{2}+\mathbf{b}^{2}-\mathbf{c}^{2}}\)

Question 4.
If sin θ + cos θ = m , show that cos⁶ θ + sin⁶ θ = \(\frac{4-3\left(m^{2}-1\right)^{2}}{4}\) where m² ≤ 2.
Answer:
sin θ + cos θ = m
(sin θ + cos θ)² = m²

Question 5.

Answer:

Question 6.

Answer:

Question 7.

Answer:

Question 8.
If tan² θ = 1 – k², show that sec θ + tan³ θ cosec θ = ( 2 – k²)^3/2. Also, find the values of k for which this result holds.
Answer:
tan² θ = 1 – k²
1 + tan² θ = 1 + 1 – k²
sec²θ = (2 – k²)
sec²θ = (2 – k²)^1/2


tan² θ = 1 – k²
When θ = \(\frac{\pi}{2}\), tan \(\frac{\pi}{2}\) = ∞, not defined 2
When θ = 0, tan² 0 = 1 – k²
1 – k² = 0 ⇒ k² = 1 ⇒ k = ± 1
When θ = 45°, tan² 45° = 1 – k²
1 – k² = 1 ⇒ – k² = 0 ⇒ k = 0
When θ > 45°, say θ = 60°
tan² 60° = 1 – k² = (√3)² = 1 – k²
3 = 1 – k² ⇒ k² = 1 – 3 = – 2
∴ θ > 45°, k² is negative ⇒ k is imaginary
∴ k lies between -1 and 1 ⇒ k ∈ [-1 , 1]

Question 9.
If sec θ + tan θ = p, obtain the values of sec θ, tan θ and sin θ in terms of p.
Answer:
Given sec θ + tan θ = p
We have sec² θ – tan² θ = 1
(sec θ + tan θ) (sec θ – tan θ) = 1
p (sec θ – tan θ) = 1
sec θ – tan θ = \(\frac{1}{p}\)
(sec θ – tan θ) + (sec θ – tan θ) = p + \(\frac{1}{p}\)

Question 10.
If cot θ(1 + sin θ) = 4m and cot θ (1 – sin θ) = 4n then prove that (m² – n²)² = mn.
Answer:

Question 11.
If cosec θ – sin θ = a³, sec θ – cos θ = b³ then prove that a²b²(a² + b²) = 1.
Answer:

Question 12.
Eliminate θ from the equations a sec θ – c tan θ = b, b sec θ + d tan θ = c.
Answer:

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 3 Trigonometry Ex 3.3 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Maths Solutions Chapter 3 Trigonometry Ex 3.3

Question 1.
Find the values of
(i) sin 480°
(ii) sin (-1110°)
(iii) cos 300°
(iv) tan (1050°)
(v) cot 660°
(vi) tan \(\left(\frac{19 \pi}{3}\right)\)
(vii) sin \(\left(\frac{-11 \pi}{3}\right)\)
Answer:
(i) sin(480°) = sin(360° + 120°) = sin 120°
= sin(90° + 30°) = cos 30° = \(\sqrt{3}\)/2

(ii) sin(-1110°) = -sin(1110°)
= – sin (360° × 3 + 30°)
= -sin 30° = -1/2

(iii) cos(300°) = cos(270° + 30°) = sin 30° = 1/2

(iv) tan (1050°)
tan (1050°) = tan(12 × 90 – 30°)
= – tan30° = – \(\frac{1}{\sqrt{3}}\)

(v) cot 660°
cot 660° = cot (7 × 90 + 30°)
= – tan 30° = – \(\frac{1}{\sqrt{3}}\)

(vi) tan \(\left(\frac{19 \pi}{3}\right)\)

(vii) sin \(\left(\frac{-11 \pi}{3}\right)\)

Question 2.
\(\left(\frac{5}{7}, \frac{2 \sqrt{6}}{7}\right)\) is a point on the terminal side of an angle θ in standard position. Determine the six trigonometric function values of angle θ.
Answer:
Given \(\left(\frac{5}{7}, \frac{2 \sqrt{6}}{7}\right)\) is a point on the terminal side of an angle θ in standard position.

Question 3.
Find the values of the other five trigonometric functions of the following
(i) cos θ = –\(\frac{1}{2}\), θ lies in the III quadrant
(ii) cos θ = \(\frac{2}{3}\), θ lies in the I quadrant
(iii) sin θ = –\(\frac{2}{3}\), θ lies in the IV quadrant
(iv) tan θ = – 2, θ lies in the II quadrant
(v) sec θ = \(\frac{13}{5}\), θ lies inthe IVquadrant
Answer:
(i) cos θ = –\(\frac{1}{2}\), θ lies in the III quadrant

(ii) cos θ = \(\frac{2}{3}\), θ lies in the I quadrant
We know that cos²θ + sin²θ = 1
\(\left(\frac{2}{3}\right)^{2}\) + sin²θ = 1
\(\frac{4}{9}\) + sin²θ = 1

Since θ lies in the I quadrant all trigonometric functions are positive.

(iii) sin θ = –\(\frac{2}{3}\), θ lies in the IV quadrant
We know that cos²θ + sin²θ = 1
cos²θ + \(\left(-\frac{2}{3}\right)^{2}\) = 1
cos²θ + \(\frac{4}{9}\) = 1

Since θ lies in the fourth quadrant cos θ is positive.

(iv) tan θ = – 2, θ lies in the II quadrant
We know that sec²θ – tan²θ = 1
sec²θ – (-2)² = 1
sec²θ – 4 = 1
sec²θ = 1 + 4 = 5
sec θ = ± √5
Since θ lies in the second quadrant sec θ is negative.

(v) sec θ = \(\frac{13}{5}\), θ lies inthe IVquadrant
We know that sec²θ – tan²θ = 1
\(\left(\frac{13}{5}\right)^{2}\) – tan²θ = 1
\(\frac{169}{25}\) – 1 = tan²θ

Question 4.
Prove that

Answer:

Question 5.
Find all the angles between 0° and 360° which satisfy the equation sin²θ = \(\frac{3}{4}\)
Answer:
sin²θ = \(\frac{3}{4}\) ⇒ sin θ = ± \(\frac{\sqrt{3}}{2}\)
sin 60° = \(\frac{\sqrt{3}}{2}\)
sin 120° = sin (180° – 60°)
= sin 60° = \(\frac{\sqrt{3}}{2}\)
∴ θ = 60° and 120°

Question 6.
Show that

Answer:

= sin² 10° + sin² 20° + [cos 20°]² + [cos 10°]²
= sin² 10° + sin² 20° + cos² 20° + cos² 10°
= sin² 10° + cos² 10° + sin² 20° + cos² 20°
= 1 + 1 = 2

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Maths Guide Pdf Chapter 3 Trigonometry Ex 3.2 Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Maths Solutions Chapter 3 Trigonometry Ex 3.2

Question 1.
Express each of the following in radian measure.
(i) 30°
(ii) 135°
(iii) -205°
(iv) 150°
(v) 330°
Answer:
(i) 30°

(ii) 135°

(iii) – 205°

(iv) 150°

(v) 330°

Question 2.
Find the degree measure corresponding to the following radian measures.
(i) \(\frac{\pi}{3}\)
(ii) \(\frac{\pi}{9}\)
(iii) \(\frac{2 \pi}{5}\)
(iv) \(\frac{7 \pi}{3}\)
(v) \(\frac{10 \pi}{9}\)
Answer:
(i) \(\frac{\pi}{3}\) radians

(ii) \(\frac{\pi}{9}\) radians

(iii) \(\frac{2 \pi}{5}\) radians

(iv) \(\frac{7 \pi}{3}\) radians

(v) \(\frac{10 \pi}{9}\) radians

Question 3.
What must be the radius of a circular running path, around which an athlete must run 5 times in order to describe 1 km?
Answer:
Let the radius of the circular path be = r m.
Length of the circular path s = 1 k. m
s = 1000 m.
Athlete runs 5 times around the path to cover 1 k. m distance
∴ θ = 360° × 5
θ = 360° × 5 × \(\frac{\pi}{180}\) radians
θ = 10 π radians
s = r θ
1000 = r 10 π
r = \(\frac{1000}{10 \pi}\)
r = \(\frac{1000 \times 7}{10 \times 22}=\frac{350}{11}\)
r = 31 .818 meters
Radius of the circular path = 31 .82 meters

Question 4.
In a circle of diameter 40 cm a chord is of length 20 cm. Find the length of the minor arc of the chord.
Answer:

Given Diameter AB = 40 cm
∴ Radius r = 20 cm
Chord CD = 20 cm
O – Centre of the circle
OC = OD = radius = 20 cm.
∴ Triangle OCD is an equilateral triangle.

To find the length of the minor arc CD.
Let s = minor arc CD.
The arc CD subtends 60° at the centre.
θ = 60°
θ = 60° × \(\frac{\pi}{180}\) radians.
θ = \(\frac{\pi}{3}\) radians
We have s = rθ

Question 5.
Find the degree measure of the angle subtended at the centre of the circle of radius 100 cm by an arc of length 22 cm.
Answer:
Given radius r = 100 cm.
Length of arc s = 22 cm.
Angle subtended by the arc at the centre = θ radians

Question 6.
What is the length of the arc intercepted by a central angle of measure 41° in a circle of radius of 10 feet?
Answer:
Central angle subtended by the arc θ = 41°
θ = 41 × \(\frac{\pi}{180}\) Radians
The radius of the circle r = 10 feet
Length of the arc = s
s = rθ

Question 7.
If in two circles, arcs of the same length subtend angles 60° and 75° at the centre, find the ratio of their radii.
Answer:
Let r₁ and r₂ be the radii of the two circles and l be the length of the arc.
Given central angle θ₁ = 60°

Question 8.
The perimeter of a certain sector of a circle is equal to the length of the arc of a semi-circle having the same radius. Express the angle of the sector in degrees, minutes, and seconds.
Answer:
Let OAB be the sector of a circle of radius r.
The angle of the sector is θ.

Perimeter of the sector = OA + arc AB + OB arc AB = rθ
∴ Perimeter of the sector = r + r θ + r
= 2r + rθ
= r(2 + θ) ———- (1)
Length of the arc of the semi – circle of radius
l = nπ ——– (2)
Given that perimeter the circular sector = Length of the arc of the semi circle of radius r
From equations (1) and (2), we have
r(2 + θ) = πr
2 + θ = π
θ = π – 2

Question 9.
An airplane propeller rotates 1000 times per minute. Find the number of degrees that a point on the edge of the propeller will rotate in 1 second.
Answer:
Given An airplane, the propeller rotates 1000 times per minute.
∴ A point on the edge of the propeller also rotates 1000 times in 1 minute.
∴ In 1 minute the point describes 1000 × 2π radians angle at the centre.
In 60 seconds the point describes 1000 × 2π radians angle.
∴ In 1 second the angle described = \(\frac{1000 \times 2 \pi}{60}\) radians

Question 10.
A train is moving on a circular track of a 1500 m radius at the rate of 66 km/hr. What angle will it turn in 20 seconds?
Answer:
Radius of the circular track r = 1500 m.
Speed of the train = 66 km/hr
Let θ be the angle made by the path of train at the centre in 20 seconds.
In 1 hr distance moved by train along the circular path = 66 km
In 60 × 60 seconds distance moved = 66 km
∴ In 20 seconds distance moved s = \(\frac{66}{60 \times 60}\) × 20

Question 11.
A circular metallic plate of radius 8 cm and thickness 6 nuns is melted and molded into a pie (a sector of the circle with thickness) of radius 16 cm and thickness 4 mm. Find the angle of the sector.
Answer:
Radius of the circular metallic plate r = 8 cm
Thickness of the plate h = 6 mm = \(\frac{6}{10}\)
Radius of the Pie l = 16 cm
Thickness of the Pie ( h) = 4mm = \(\frac{4}{10}\) cm
Given volume of the cylinder = Volume of the sector

Tamilnadu State Board New Syllabus Samacheer Kalvi 9th Science Guide Pdf Chapter 4 Electric Charge and Electric Current Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 9th Science Solutions Chapter 4 Electric Charge and Electric Current

9th Science Guide Electric Charge and Electric Current Text Book Back Questions and Answers

I. Choose the correct answer:

Question 1.
In current electricity, a positive charge refers to,
(a) presence of electron
(b) presence of proton
(c) absence of electron
(d) absence of proton
Answer:
(c) absence of electron

Question 2.
Rubbing of comb with hair
(a) creates electric charge
(b) transfers electric charge
(c) either (a) or (b)
(d) neither (a) nor (b)
Answer:
(b) transfers electric charge

Question 3.
Electric field lines ……………….. from positive charge and ……………………..in negative charge.
(a) start; start
(b) start; end
(c) start: end
(d) end; end
Answer:
(b) or (c) start, end

Question 4.
Potential near a charge is the measure of its……………to bring a positive charge at that point.
(a) force
(b) ability
(c) tendency
(d) work
Answer:
(d) work

Question 5.
Heating effect of current is called,
(a) Joule heating
(b) Coulomb heating
(c) Voltage heating
(d) Ampere heating
Answer:
(a) Joule heating

Question 6.
In an electrolyte, the current is due to the flow of
(a) electrons
(b) positive ions
(c) both (a) and (b)
(d) neither (a) nor (b)
Answer:
(c) both (a) and (b)

Question 7.
Electroplating is an example of
(a) heating effects
(b) chemical effects
(c) flowing effects
(d) magnetic effect
Answer:
(b) chemical effect

Question 8.
Resistance of a wire depends on,
(a) temperature
(e) nature of material
(b) geometry
(d) all the above
Answer:
(d) all the above

II. Match the following

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

III. State whether true or false. If false, correct the statement:

1. Electrically neutral means it is either zero or equal positive and negative charges.
Answer:
True.

2. Ammeter is connected in parallel in an electric circuit.
Answer:
False.
Correct statement: Ammeter is connected in series in an electric circuit.

3. The anode in the electrolyte is negative.
Answer:
False.
Correct statement: The anode in the electrolyte is positive.

4. Current can produce the magnetic field.
Answer:
True.

IV. Fill in the blanks :

1. Electrons move from …………….. potential to …………….. potential.
Answer:
lower, higher

2. The direction opposite to the movement of electron is called …………….. current.
Answer:
conventional

3. The e.m.f of a cell is analogues to a pipeline.
Answer:
water pump

4. The domestic electricity in India is an ac with a frequency of Hz.
Answer:
50

V. Conceptual Questions:

Question 1.
A bird sitting on a high power electric line is still safe. How?
Answer:
Birds don’t get shocked when they sit on electrical wires because they are not good conductors of electricity. Electricity flowing through a single power line at 35,000 volts will continue along the path of least resistance and bypass birds because there is no difference in electrical potential.

Question 2.
Does a solar cell always maintain the potential across its terminals constant? Discuss.
Answer:
Solar cell delivers a constant current for any given illumination level, while the voltage is determined by the load resistance. Potential in a solar cell depends on the intensity of solar radiation. Since the intensity of solar radiation is not always constant, the potential across its terminal is also not constant.

Question 3.
Can electroplating be possible with the alternating current?
Answer:
Electroplating is a process where there is a continuous flow of ions for the deposition of copper, which is not possible in an Alternating current. Therefore, electroplating is possible with DC only, for the sake of perfectness and homogeneity of the electroplating.

VI. Answer the following:

Question 1.
On what factors does the electrostatic force between two charges depend?
Answer:
The electrostatic force between two charges depend on the following factors;

• value of charges on them,
  
• distance between them, and
  
• nature of medium between them.

Question 2.
What are the electric lines of force?
Answer:
The lines representing the electric field are called electric lines of force.

Question 3.
Define electric field.
Answer:
The electric lines of force are straight or curved paths along which a unit positive charge tends to move in the electric field.

Question 4.
Define electric current and give its unit.
Answer:
The electric current is defined as the rate of flow of electric charge through any section of a conductor.
Electric current I = Q/t
Its unit is Cs^-1
Its SI unit: ampere (A).

Question 5.
State Ohm’s law.
Answer:
Ohm’s law states that electric potential difference across two points in an electrical circuit is directly proportional to the current passing through it. That is V ~ I
The proportionality constant is the resistance (R) offered between the two points.
Hence, Ohm’s law is written as V = RI (or) V = IR
Where, V is the potential difference in volt (V), I is the current flow in ampere (A), R is the resistance in ohm (Ω)

Question 6.
Name any two appliances which work under the principle of heating effect of current.
Answer:
Electric heating appliances like an iron box, water heater, toaster, etc.

Question 7.
How are the home appliances connected in general, in series or parallel? Give reasons.
Answer:
The home appliances are connected in parallel. This is because, when the appliances are connected in parallel, each of them can be switched on and off independently. This is a feature that is essential in house wiring. Also, if the appliances were wired in series, the potential difference across each appliance would vary depending on the resistance of the appliance.

Question 8.
List the safety features whilehandling electricity.
Answer:
(i) Ground connection: The metal bodies of all the electrical appliances are to be connected to the ground by means of a third wire apart from the two wires used for electrical connection.

(ii) Trip switch: It is an electromechanical device which does not allow a current beyond a particular value by automatically switching off the connection.

(iii) Fuse: A fuse is another safety mechanism which works on the joule heating principle.

VII. Exercises:

Question 1.
Rubbing a comb on hair makes the comb get – 0.4C.
(a) Find which material has lost electron and which one gained it.
(b) Find how many electrons are transferred in this process.
Answer:
a. Comb gained electrons. Dry hair lost an electron
b. No. of electrons transferred = -0.4 C
1 coulomb = 6.25 × 10¹⁸ electron
– 0.4 C = 0.4 × 6.25 × 10¹⁸ electrons
= -2.5 × 10¹⁸ electrons

Question 2.
Calculate the amount of charge that would flow in 2 hours through an element of an electric bulb drawing a current of 2.5A.
Answer:
Current I = 2.5 A
time t = 2 hours = 2 × 3600 seconds
t = 7200 s
Amount of charge Q = I × t = 2.5 × 7200
Q = 18,000

Question 3.
The values of the current (I) flowing through a resistor for various potential differences V across the resistor are given below. What is the value of resistor?

[Hint: plot V-I graph and take slope]
Answer:

Intext Activities

ACTIVITY – 1

Take a condemned electronic circuit board in a TV remote or old mobile phone. Look at the electrical symbols used in the circuit. Find out the meaning of the symbols known to you.


[End of the activity]

ACTIVITY – 2
Cut an arrow shaped strip from aluminium foil. Ensure that the head is a fine point. Keep the arrow shaped foil on a wooden board. Connect a thin pin to two lengths of wire. Connect the wires to the terminals of electric cell, may be of 9V. Press one pin onto the pointed tip and the other pin at a point about one or two mm away. Can you see that the tip of aluminum foil starts melting?

Aim :
To understand the heating effect of electric current.

Materials Required :
Aluminum strip, wooden board, bell pins, cell of 9 V.

Procedure :
Cut an arrow shaped strip from aluminum foil. Keep the arrow shaped foil on a wooden board. Connect a pin to two lengths of wire. Connect the wires to the terminals of electric cell of 9 V. Press one pin onto the pointed tip and another pin at a point about one or two mm away.

Observation :
The tip’of aluminum foil starts melting.

Conclusion :
It starts melting because the electrons while moving in the wire suffer resistance. Work is done to overcome the resistance which is converted into heat energy. This conversion of electrical energy into heating energy is called the heating effect of electric current.

ACTIVITY – 3

Take a beaker half filled with copper sulphate solution. Take a carbon rod from a used dry cell. Wind a wire on its upper end. Take a thick copper wire, clean it well and flatten it with a hammer. Immerse both the copper wire and carbon rod in the copper sulphate solution. Connect the carbon rod to the negative terminal of an electric cell and copper wire to the positive terminal of the cell. Also ensure that the copper and the carbon rod do not touch each other, but are close enough. Wait and watch. After some time you would find fine copper deposited over the carbon rod. This is called as electroplating. This is due to the chemical effect of the current.

Aim:
Electroplating carbon rod with copper.

Materials Required:
Beaker, copper sulphate solution, carbon rod, thick copper wire and hammer.

Procedure :

• Take a beaker half filled with copper sulphate solution.
• Take a carbon rod and wind a wire on its upper end.
• Take a thick copper wire, clean it well and flatten it with a hammer.
• Immerse both the copper wire and carbon rod in the copper sulphate solution.
• Connect the carbon rod to the negative terminal of the cell and copper wire to the positive terminal of the cell.
• Ensure both the rods do not touch each other, but are close enough.
• Observe for some time.

Observation :
After some time, we would find fine copper deposited over the carbon rod.

Conclusion :
When the current passes through the copper sulphate solution, the copper ions migrate from the copper sulphate solution towards the cathode (-ve terminal). These copper ions get deposited on the carbon rod and form a coating of a fine layer on it.

This process of coating a metal over another metal by electrolysis is called electroplating. This is due to the chemical effect of electric current.

9th Science Guide Electric Charge and Electric Current Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
A current of 2A passing through the conductor produces 80 J of heat in 10 seconds. The resistance of the conductor is ……………..
(a) 0.5Ω
(b) 2Ω
(c) 4Ω
(d) 20Ω
Answer:
(b) 2Ω

Question 2.
The resistance of a straight conductor is independent of …………………..
(a) temperature
(b) material
(c) cross sectional area
(d) shape of cross section
Answer:
(d) shape of cross section

Question 3.
Two resistances R1 and R2 are connected is parallel. Their equivalent resistance is


Answer:

Question 4.
If in the circuit, power dissipation is 150 W, then R is ……………..

(a) 2Ω
(b) 6Ω
(c) 5Ω
(d) 4Ω
Answer:
(b) 6Ω

Question 5.
The force between two parallel wires carrying currents has been used to define…………..
(a) ampere
(b) coulomb
(c) volt
(d) watt
Answer:
(a) ampere

Question 6.
Electric current passes through a metallic conductor due to the movement of ……………
(a) ions
(b) ampere
(c) electrons
(d) protons
Answer:
(c) electrons

Question 7.
What is the maximum resistance one can make with ten 1Ω resistors?
(a) 1Ω
(b) 2Ω
(c) 5Ω
(d) 10Ω
Answer:
(d) 10Ω

Question 8.
Two conductors of resistance 2 R and R are connected in series in a battery circuit. The ratio of heat developed In them is ……………………
(a) 2 : 1
(b) 1 : 2
(c) 1 : 3
(d) 1 : 4
Ans:
(a) 2 : 11

Question 9.
1 volt = …………..


Answer:

Question 10.
The resistance of a conductor is R. If Its length is doubled, then its new resistance will be ……………….
(a) R
(b) 2R
(c) 4R
(d) 8R
Answer:
(C) 4R

Question 11.
The following is not a safety device.
(a) Fuse
(b) Trip switch
(c) Ground connection
(d) Wire
Answer:
(d) wirel

Question 12.
In India the frequency of alternating current is,
(a) 220 Hz
(b) 50 Hz
(c) 5 Hz
(d) 100 Hz
Answer:
(b) 50 Hz

II. Fill in the blanks:

1. The number of electrons constituting 1-coulomb charge is………………….
Answer:
6.25 × 10¹⁸

2. Resistors are connected in series if the resistance of the electric circuit is to be………………….
Answer:
increased

3. Electric fuse is a wire made up of a material having ………………….melting point.
Answer:
low

4. ………………….is the only non-metal that is a good conductor of electricity.
Answer:
Graphite

5. If the area of cross section of the conductor is doubled its resistance gets ………………….
Answer:
halved

6. A negative charge will move from …………………. to …………………. potential.
Answer:
lower, higher

7. ………………….is work done per unit charge.
Answer:
Potential difference

8. An electrochemical cell converts …………………. energy into …………………. energy.
Answer:
chemical, electrical

9. Three resistors are connected in series with a cell. If the current in each resistor is 1.5A, then the current through the cell will be ………………….. Answer:
1.5A

10. Three resistors are connected in parallel with a battery. If the current in each resistor is 2A, then the current through the battery will be …………………..
Answer:
6A

11. As electrons are revolving in the ………………….of an atom they can be easily removed from an atom and also added to it.
Answer:
orbits

12. If an electron is added in excess to an atom then the atom is ………………….charged.
Answer:
negatively

13. The excess of electrons make an object negative and ………………….of electrons make it positive.
Answer:
deficit

14. Electric charge is ………………….in nature.
Answer:
additive

15. Electric lines of force are ………………….lines.
Answer:
imaginary

16. For an isolated positive charge the electric lines of force are radial…………………. and for an isolated negative charge they are radial…………………..
Answer:
outwards, inwards

17. ………………….at a point is a measure of force acting on a unit positive charge placed at that point.
Answer:
Electric field

18. Electric potential is a measure of the ………………….on the unit positive charge to bring it to that point against all electrical forces.
Answer:
work done

19. The movement of positive charge is called as ………………….
Answer:
conventional current

20. The …………………. is the measure of opposition offered by the component to the flow of electric current through it.
Answer:
resistance

21. The process of conduction of electric current through solution is called………………….
Answer:
electrolysis

22. The device used to convert AC to DC is called………………….
Answer:
rectifier

23. Trip switch is a …………………. safety device.
Answer:
electro mechanical

III. True or False:

1. A fuse is used in an electric circuit to stop high current flowing through the circuit.
Answer:
True.

2. Rheostat is also known as fixed resistance.
Answer:
False.
Correct statement: Rheostat is also known as a variable resistance.

3. An ammeter is always placed in parallel with the circuit.
Answer:
False.
Correct statement: An ammeter is always placed in series with the circuit.

4. The resistance of a dry human body is high.
Answer:
True.

5. For current to flow, one needs art open circuit.
Answer:
Correct statement: For current to flow, one needs a closed circuit.

6. A comb rubbed with hair and brought near pieces of paper attracts them, because both comb and paper get similarly charged.
Answer:
False.
Correct statement: A comb rubbed with hair and brought near pieces of paper attracts them, because both comb and paper get oppositely charged.

7. Overloading of electric circuits can lead to short-circuiting.
Answer:
True.

8. Electrons in outer orbits are called free electrons.
Answer:
True.

9. Electric fuse works on the Joule heating principle.
Answer:
True.

IV. Match the following:

I.

Answer:
1-d, 2-c, 3 -a, 4-b

II.

Answer:
1-c, 2-d, 3-c, 4-a

V. Assertion and Reason type questions :

Mark the correct choice as :
(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c) If assertion is true but reason is false.
(d) If assertion is false but reason is true.

Question 1.
Assertion (A): Electric current will not flow between two charged bodies when connected if their charges are the same.
Reason (R): Current is the rate of flow of charge.
Answer:
(d) Assertion is false but the reason is true
Reason: Current will not flow when two bodies are at the same potential. When their charges are the same, their potential may be different. Hence current may flow in this case.

Question 2.
Assertion (A) : A bird perches on a high power line and nothing happens to the bird.
Reason (R) : The level of the bird is very high from the ground.
Answer:
(c) Assertion is true but reason is false
Reason: Electric shock is due to the electric current flowing through a living body. When the bird perches on a single high power line, no current passes through its body. Because its body is at an equipotent surface (i.e.) there is no potential difference. While when a man touches the same line, standing bare foot on the ground the electrical circuit is completed through the ground. The hands of man are at high potential and his feet are at low potential. Hence the large amount of current flows through the body of the man and the person, therefore, gets a fatal shock.

VI. Answer in one word:

Question 1.
Name the force which acts between two point charges obey Newton’s third law.
Answer:
Electrostatic force.

Question 2.
What is the SI unit for the current?
Answer:
ampere (A).

Question 3.
Name the device which is used to measure the strength of the electric current in an electric circuit.
Answer:
Ammeter.

Question 4.
What is the rate at which charges flow past a point on a circuit?
Answer:
Current.

Question 5.
Name a device that helps to maintain a potential difference across conductors.
Answer:
Cell or battery.

Question 6.
What does the circuit symbol represent?
Answer:
Wire crossing without touching each other.

Question 7.
How many electrons accumulate to make 1C of electric charge?
Answer:
1C = 6.25 × 10¹⁸ electrons.

Question 8.
What is the charge of one electron?
Answer:
e= 1.6 × 10^-19C.

Question 9.
What is the measure of the work done on the unit positive charge to bring it to that point against all electrical forces?
Answer:
Electric potential

Question 10.
How is a voltmeter connected in the circuit to measure the potential difference between two points?
Answer:
Parallel

VII. Subjective Problems:

Question 1.
Calculate the charge passing through a lamp in 2 minutes if the current is 3A.
Solution:
Current I = 3A
Time t = 2 minutes = 120seconds
Charge q = ?
q = I × t = 3 × 120
Charge q = 36.C

Question 2.
Calculate the current in a wire if a charge of 1500 coulomb flows through it in 5 minutes.
Solution:
Charge q = 1500 C
Time t = 5 minutes = 300 seconds
Current I =?
I = q/t = \(\frac{1500}{300}\)
Current I = 5A

Question 3.
A charge of 400C flows through a conductor for 13 minutes and 20 seconds. Find the magnitude of the current flowing through the conductor.
Answer:
Q = 400C
t = 13 min and 20s = 13 × 60 + 20
= 780 + 20
= 800s
Current I = \(\frac{Q}{t}=\frac{400}{800}=0.5 \mathrm{A}\)

Question 4.
10²⁰ electrons, each having a charge of 1.6 x 10^-19 C, flows in a circuit V is 0.1s. What is the current in ampere?
Solution :
n = 10²⁰ electrons
e = 1.6 × 10^-19C
t = 0.1s
Charge q = ne
= 10²⁰ × 1.6 × 10^-19
= 16C
Current I = \(\frac{q}{t}=\frac{16}{0.1}=160 \mathrm{~A}\)
∴ Current = 160 A

VIII. Long Answer Questions

Question 1.
a State Ohm’s law.
b. Draw a circuit diagram for the verification of ohm’s law. Also, plot graphically the variation of current with a potential difference.
Answer:
a. Ohm’s law states that the current passing through a conductor is directly proportional
to the potential difference a cross its ends, provided the physical conditions like temperature density etc. remain unchanged V ∝ I or V = IR.
b.

Question 2.
a. Why is series arrangement not used for domestic cricuits?
b. Explain why fuse wire is always connected in series arrangement.
c. Why are copper and aluminium wires useually employed for electricity transmission?
Answer:
a. Series arrangement is not used for domestic circuits because same current will flow through all the appliances. The equivalent resistance will get added and hence the current drawn by the circuit will be less.

b. Fuse wire is always connected in series in a circuit as it has to check the flow of current through the circuit and prevent the extra flow of current through it.

c. Fuse wire is always connected in series in a circuit as it has to check the flow of current through the circuit and prevent the extra flow of current through it.

Question 3.
Explain the dangers of electricity and precautions to be taken while handling electricity.
Answer:

• Damaged insulation – Do not touch the bare wire, use safety gloves, and stand on an insulating stool or rubber slippers while handling electricity.
• Overheating of cables – use quality ISI certified cable wires for domestic wiring
• Overload of power sockets – do not connect too many electrical devices to a single electrical socket.
• Inappropriate use of electrical appliances – always uses the electrical appliances according to the power rating of the device like AC point, TV point, microwave oven point, etc.
• Environment with moisture and dampness – keep the place where there is electricity out of moisture and wetness as it will lead to leakage of electric current.
• Beyond the reach of children – the electrical sockets are to be kept away from the reach of little children who do not know the dangers of electricity.

Question 4.
Write the difference between resistance in series and in parallel.
Answer:

IX.

Question 1.
Distinguish e.m.f and potential difference.
Answer:
As both e.m.f and potential difference are measured in volt, they may appear the same. But they are not. The e.m.f refers to the voltage developed across the terminals of an electrical source when it does not produce current in the circuit. Potential difference refers to the voltage developed between any two points (even across electrical devices) in an electric circuit when there is current in the circuit.

Question 2.
Some common symbols in the electrical circuit.
Answer:

Question 3.
Write a note on direct current.
Answer:

• Current in electrical circuits is due to the motion of positive charge from higher potential to lower potential or electron from lower to higher electrical potential.
• Electrons move from negative terminal of the battery to positive of the battery. Battery is used to maintain a potential difference between the two ends of the wire.
• Battery is one of the sources for dc current. The dc is due to the unidirectional flow of electric charges. Some other sources of dc are solar cells, thermocouples etc. The graph depicting the direct current is shown in Figure.
  
• Many electronic circuits use dc. Some examples of devices which work on dc are cell phones, radio, electric keyboard, electric vehicles etc.

Question 4.
Write a note on alternating current.
Answer:

• If the direction of the current in a resistor or in any other element changes its direction alternately, the current is called an alternating current.
• The alternating current varies sinusoidally with time. This variation is characterised by a term called as frequency.
• Frequency is the number of complete cycle of variation, gone through by the ac in
  one second. s
• In ac, the electrons do not flow in one direction because the potential of the terminals vary between high and low alternately.
• Thus, the electrons move to and fro in the wire carrying alternating current. It is diagrammatically represented in Figure

Question 5.
Explain the advantages of Ac over Dc.
Answer:

• The voltage of ac can be varied easily using a device called transformer. The ac can be carried over long distances using step-up transformers.
• The loss of energy while distributing current in the form of ac is negligible. Direct current cannot be transmitted as such.
• The ac can be easily converted into dc and generating ac is easier than dc
• The ac can produce electromagnetic induction which is useful in several ways.

X. Define the following:

1. Electric force: The force existing between the charges is called an ‘electric force’.
2. Electric potential: Electric potential is a measure of the work done on the unit positive charge to bring it to that point against all electrical forces.
3. Conventional current and electron current: The movement of the positive charge is called as ‘conventional current’. The flow of electrons is termed as ‘electron current’.
4. Current: Current is the rate at which charges flow past a point on a circuit.
5. Electromotive force (e.m.f.): The e.m.f of an electrical energy source is one volt if one joule of work is done by the source to drive one coulomb of charge completely around the circuit.
6. One ohm: One ohm is the resistance of a component when the potential difference of one volt applied across the component drives a current of one ampere through it.
7. Fixed resistor: A fixed resistor has a resistance of a fixed value. Common types of fixed resistors include carbon film resistors and wire-wound resistors.
8. Variable resistor: A variable resistor has a resistance that can be varied. It is used to vary the amount of current flowing in a circuit.
9. Electrolysis and electrolyte: The process of conduction of electric current through solutions is called ‘electrolysis’. The solution through which the electricity passes is called ‘electrolyte’.
10. Synaptic signals: Extremely weak electric current is produced in the human body by the movement of charged particles. These are called synaptic signals. These signals are produced by the electrochemical process. They travel between the brain and the organs through the nervous system.
11. Magnetic effect of current: A wire or a conductor carrying current develops a magnetic field perpendicular to the direction of the flow of current. This is called the magnetic effect of current.
12. Frequency: Frequency is the number of the complete cycle of variations, gone through by the ac in one second.
13. Rectifier: The device used to convert ac to dc is called a rectifier.
14. Resistance: The measure of opposition offered by the component to the flow of electric current through it.
15. Resistors: The components used for providing resistance are called resistors.

Tamilnadu State Board New Syllabus Samacheer Kalvi 4th English Guide Pdf Term 3 Poem 1 Be Honest Text Book Back Questions and Answers, Summary, Notes.

Tamilnadu Samacheer Kalvi 4th English Solutions Term 3 Poem 1 Be Honest

4th English Guide Be Honest Text Book Back Questions and Answers

A. Match the rhyming words.

Question 1.
Say – grow
Answer:
Say – day

Question 2.
All – time
Answer:
All – fall

Question 3.
Go – day
Answer:
Go – grow

Question 4.
Rhyme – fall
Answer:
Rhyme – time

B. Fill in the blanks.

Question 1.
_________ will often say to be honest.
Answer:
Amma

Question 2.
We shouldn’t __________ ever.
Answer:
Lie

Question 3.
Many may lie and __________.
Answer:
Go

C. Answer the questions.

Question 1.
What makes him fall?
Answer:
Troubles make him fall.

Question 2.
What does Amma often say?
Answer:
Amma will often say to be honest every day.

Question 3.
What will help us grow?
Answer:
Honesty will help us to grow.

Question 4.
What will help you say the truth?
Answer:
Honesty will help us to say the truth.

Question 5.
Do you tell the truth always? Why?
Answer:
Telling the truth always is not possible. It depends on the situation. If thieves come to our house and ask where are the jewels, is it correct to tell the truth at that situation?

I. Fill in the blanks.

Question 1.
I want to be __________ to all.
Answer:
Truthful

Question 2.
Honesty will help us __________.
Answer:
Grow

Question 3.
__________ make me fall.
Answer:
Troubles

II. Answer the questions.

Question 1.
How does the poet want to be?
Answer:
The poet wants to be truthful to all.

Question 2.
What does Amma say when she hears others lie?
Answer:
Amma says that people may lie and go but we must tell the truth and grow.

Let us know

We have already learnt to use a, an and the. Can you try to fill the blanks below with a, an and the?

Question 1.

This is __________ ball.
Answer:
A

Question 2.

There is _________ ink bottle.
Answer:
The

Question 3.

__________ sun is hot.
Answer:
The

Question 4.

This is __________ owl.
Answer:
An

Write ‘a’ or ‘an’

Question 1.

__________ book.
Answer:
A

Question 2.

__________ ant.
Answer:
An

Question 3.

___________ chair.
Answer:
A

Question 4.

__________ egg.
Answer:
An

Question 5.

__________ pot.
Answer:
A

Question 6.

___________ flag.
Answer:
A

Question 7.

__________ inn.
Answer:
An

Question 8.

___________ unicorn.
Answer:
A

Fill in the blanks using a, an and the.

Question 1.
_________ Earth goes around _________ Sun.
Answer:

1. The
2. The

Question 2.
I bought __________ pair of shoes.
Answer:
A

Question 3.
I am _________ university student.
Answer:
A
[Hint : Here, the letter ‘u’ in the word university, is to be pronounced as “Yu”. So, ‘a’ is used before “university”]

Question 4.
Kiran sails in __________ Indian ocean.
Answer:
The

Question 5.
__________ camel is the ship of _________ desert.
Answer:

1. The
2. The

Question 6.
________ Jungle book has won many awards.
Answer:
The

Question 7.
Harichandra was __________ honest king.
Answer:
An
[Hint : Here, the letter ‘h’ is silent. Hence, an honest.]

Question 8.
I met _________ boy in the street.
Answer:
A

Question 9.
She returned after __________ hour.
Answer:
An
[Hint : Here, the letter ‘h’ is silent. Hence, an hour.]

Question 10.
I read _________ amazing story yesterday.
Answer:
An

Fill in with the correct aticles. Additional Questions and Answers

Question 1.
The police were looking for _________ arrogant thief.
Answer:
An

Question 2.
He tried to rob ________ cell phone shop with ________
Answer:

1. A
2. A

Question 3.
The thief threw _________ old bag at ________ shop keeper.
Answer:

1. An
2. The

Question 4.
He ordered him to fill ___________ bag with money.
Answer:
The

Question 5.
The shop keeper was not sure if ___________ gun was real or not.
Answer:
The

Let us speak

Question 1.
See how they speak at this situation and practise as if you were in that situation. A teacher is teaching the class.
Answer:

Teacher : In today’s class we are going to learn about verbs.
Student : Okay miss.
Teacher : Verbs are action words, they tell us what action is happening or going to happen.
Student : Miss, I have a doubt.
Teacher : What is the doubt?
Student : What is an action miss?
Teacher : An action is anything we do. Like now I am standing, you are sitting. We eat during the lunch. All such words are action words. Student : Got it, miss. Thank you.
Teacher : Welcome.

Additional question

Question 1.
A friend tells you the route to the post office – Write how they speak at this situation and express as if you were in that situation.
Answer:
Raja : Can you tell me how to go to the post office?
Rani : Sure, I will! Raja.
Raja : Rani, I have a doubt.
Rani : What is the doubt?
Raja : Is the post office right or left side to our school?
Rani : It is not in the left or right, it is behind our school.
Raja : I could not understand. Can you please explain?
Rani : Sure Raja. If you walk around our school, the post office is at the back of our school.
Raja : Now I got it Rani. Thank you very much!
Rani : You are most welcome Raja.

Be Honest Summary in English and Tamil

Amma will often say,
Be honest all day!
Still troubles make me fall,
I want to be truthful to all!
Amma will often say,
Be honest every day!
To say truth when I am wrong,
I may have to be eighteen!
To Amma I often say,
Don’t you hear them lie?
She says many may lie and go
But honesty will help us grow!
At last, I have this to say,
I don’t lie to this day!
The trick is the rhyme,
Let’s try this one day at a time!

நேர்மையாக இருங்கள் அம்மா எப்போதும் கூறுவார்,
ஒவ்வொரு நாளும் நேர்மையாய் இரு என்று!
அப்படியும் பிரச்சனைகள் என்னை விழவைக்கும்,
நான் அனைவருக்கும் உண்மையாய் இருக்க விரும்புகிறேன்!
அம்மா அடிக்கடி கூறுவார்,
ஒவ்வொரு நாளும் நேர்மையாய் இரு என்று!
நான் தவறு செய்யும்போது, உண்மையைக் கூறவேண்டும்.
எனக்கு பதினெட்டு வயதாகியும் இருக்கலாம்.
அம்மாவிடம் நான் அடிக்கடி கூறுவேன்
அவர்கள் பொய் பேசுவதை நீ கேட்பதில்லையா?
“பலர், பொய்களை கூறிவிட்டு போகலாம்,
ஆனால், நேர்மை நம்மை உயர்த்திட உதவும்,” என்கிறார் அம்மா.
கடைசியாக, இதை நான் கூறுகிறேன்
இன்றுவரை நான் பொய் பேசியதில்லை!
அந்த நுட்பம் என்பது அந்த சந்த நயம்,
ஒருநாள், ஒரே சமயத்தில் நாம் இதைச் செய்ய முயலுவோம்!

Be Honest Glossary

Grow – improve (வளருதல்)
Honest – truthful (நேர்மை)
Lie – a false statement (பொய்)
Often – frequently (அடிக்கடி)
Troubles – difficulty or problem (பிரச்சனைகள்)
Trick – technique (நுட்பம், உத்தி)

Tamilnadu State Board New Syllabus Samacheer Kalvi 12th English Guide Pdf  Poem 1 The Castle Text Book Back Questions and Answers, Summary, Notes.

Tamilnadu Samacheer Kalvi 12th English Solutions Poem 1 The Castle

12th English Guide The Castle Text Book Back Questions and Answers

Textual Questions:

1. Based on your understanding of the poem, answer the following questions in one or two sentences each:
(Text Book Page No. 20)

Question a.
who is the narrator in the poem?
Answer:
A soldier is a narrator in the poem.

Question b.
How long had the soldiers been in The Castle?
Answer:
All through the summer, the soldiers had been in The Castle.

Question c.
why were the soldiers in The Castle fearless?
Answer:
They were fearless because they were behind a well-guarded castle headed by a brave captain. Allies were close at hand and they had adequate arms to fight and foodgrains to sustain them under a siege.

Question d.
Where were the enemies?
Answer:
The enemies were half a mile away from The Castle.

Question e.
Why does the narrator say that the enemy was no threat at all?
Answer:
Soldiers behind the turret wall were ready to shoot the enemy at sight. The castle was surrounded by a deadly moat. The captain was brave and the soldiers loyal. Allies were close at hand. Hence, the enemy was no threat at all.

Question f.
Did the soldiers fight with the enemies face to face?
Answer:
No, The soldiers did not fight with the enemies face to face.

Question g.
Who had let the enemies in?
Answer:
The aged greedy wicket gate keeper had let the enemy in.

Question h.
How did the enemies enter The Castle?
Answer:

1. The disloyal warder, who guards the wicket gate, let the enemies inside the famous citadel for gold.
2. Thus the enemies entered The Castle.

Question i.
Why were the secret galleries bare?
Answer:
The secret galleries were looted by the cunning enemies. So, they were bare.

Question j.
What was the ‘shameful act’?
Answer:
The disloyal warder, who guards the wicket gate, let the enemies inside the famous citadel for gold. This was the shameful act.

Question k.
Why didn’t the narrator want to tell the tale to anybody?
Answer:
The narrator did not want to tell the shameful act because it will expose the greed of the aged warder. He had sold them all for a bag of gold. They did not have any weapon to fight the invisible enemy within.

Question l.
Why did the narrator feel helpless?
Answer:

1. The narrator’s troop and castle were defeated by all the enemies.
2. He could not accept this treacherous defeat. So he felt helpless.

Question m.
Who was the real enemy?
Answer:
“The gold” was their real enemy.

2. Read the poem again and complete the summary using the words given inbox. (Text Book Page No. 21)

Question 1.
Stanzas 1-3:
The Castle’ by Edwin Muir is a moving poem on the (1) ______ of a well-guarded (2)______. The soldiers of The Castle were totally stress-free and relaxed. They were (3)______ of their castle’s physical strength. Through the turrets, they were able to watch the mowers and no enemy was found up to the distance of (4)______ and so they seemed no threat to The Castle. They had (5)______ of weapons to protect them and a large quantity of (6)______ in stock to take care of the well-being of the soldiers inside The Castle. The soldiers stood one above the other on the towering (7)______ to shoot the enemy at sight. They believed that The Castle was absolutely safe because their captain was (8)______ and the soldiers were loyal.

Answer:

1. Capture
2. Castle
3. Confident
4. half-a-kilometer
5. Plenty
6. Ration
7. Watching
8. Brave

Question 2.
Stanzas 4-6:
Even by a trick, no one but the birds could enter. The enemy could not use a (9)______ for their entry inside The Castle. But there was a wicket gate guarded by a (10)______. He (11)______ in the enemies inside the famous citadel that had been known for its secret gallery and intricate path. The strong castle became(12)______ and thin because of the greedy disloyal warder. The (13)______ was captured by the enemies for (14)______. The narrator (15)______ over the (16)______ of the useless warder and also decided not to disclose this (17)______ story to anyone. He was (18)______ and wondered how he would keep this truth to himself. He regretted not finding any (19) to fight with the (29)______ called ‘gold’.

Answer:
9. Bail
10. wicked guard
11. let
12. helpless
13. citadel
14. disloyalty
15. lamented
16. weak
17. shameful
18. gold
19. weapon
20. enemy

3. Read the poem and answer the following in a short paragraph of 8-10 sentences each: (Text Book Page No.. 21)

Question a.
How safe was The Castle? How was it conquered?
Answer:

Introduction:
The poet Edwin Muir beautifully brings out the strength of The Castle.

Safety of The Castle:
The soldiers did not worry about threats around them because The Castle gates were strong and walls were high, thick, and smooth. They felt very safe because they had more confidence towards The Castle. They trusted a lot that even by a trick no one could enter The Castle. The human beings did not have the courage to enter The Castle but birds could enter. So the soldiers were in a relaxed manner and stress-free about everything around them.

The belief of the soldiers:
They believed that The Castle was absolutely safe and because of its physical strength and their captain was brave and the soldiers were loyal.

Disloyal warder:
The strong castle became helpless and thin. The soldiers unexpectedly faced failure because of the greedy disloyal warder. The famous citadel was captured by the enemies for disloyalty (gold). The black sheep was one of their own men (warder) who let the enemies inside the citadel that had been known for its secret gallery and intricate path.

Conclusion:
Once, The Castle was safe because soldiers were united and loyal and their captain was brave. But later disloyalty arose from their own men warder, The Castle was conquered by the enemies.
Greedy kills humanity.

Question b.
Bring out the contrasting picture of the as depicted in stanzas 3 and 5.
Answer:
The poet Edwin Muir beautifully brings out the strength of The Castle. The soldiers did not worry about threats around them because The Castle gates were strong and walls were high, thick, and smooth. They felt very safe because they had more confidence towards The Castle. They trusted a lot that even by a trick no one could enter The Castle. The Castle was very high and smooth. So human beings did not have the courage to enter The Castle but birds could enter. Birds were harmless to them.

So the soldiers were in a relaxed manner and stress-free about everything around them. They believed The Castle was absolutely safe because their captain was brave and the soldiers were loyal. They only focussed on the strength of physical surroundings and what was beyond The Castle but betrayed from within caused The Castle’s fall. The strong castle became helpless and thin. The famous citadel was captured by the enemies for disloyalty.

The warder had let the enemies inside the famous citadel that had been known for its secret gallery and intricate path. Once The Castle was safe because soldiers were united and loyal and their captain was brave. Later disloyalty arose from their own men warder, The Castle was conquered by the enemies.

Question c.
Human greed led to the mighty fall of the citadel. Explain.
Answer:
Greed means a selfish or excessive desire for more than is needed or deserved, especially of money, wealth, food, or other possession. One who is greedy follows the path of unfair means, betrayal, and crime. This makes other’s life miserable. “Greed’ can also mean helping an enemy, such a person who gives secret information to an enemy country. That brings the mighty fall of the kingdom.

Here, In the poem ‘The Castle’, a greedy warder was the main cause and culprit who brought failure to his own men. Before that, the soldiers were stress-free and relaxed. They have plenty of arms and food. The Castle gates were strong and walls were high, thick, and smooth. They believed that The Castle was absolutely safe because their captain was brave and the soldiers were loyal.

Yet these men were defeated when the enemy entered to their own man (warder) who let the enemy soldiers through a little gate. At first, The Castle was safe because soldiers were the united castle and loyal and their captain was brave. But later, The Castle became weak and thin. As disloyalty arose from their own men, warder, The Castle was conquered by the enemies.
‘Greed kills humanity’. Thus human greed led to the mighty fall of the citadel.

4. Read the given lines and answer the questions that follow in a line or two: (Text Book Page No. 21)

a. All through the summer at ease we lay,
And daily from the turret wall,
we watched the mowers in the hay.

i. Who does ‘we’ refer to?
Answer:
‘We’ refer to soldiers who are in a strong castle.

ii. How did the soldiers spend the summer days?
Answer:
The soldiers spent the summer days lying and relaxing.

iii. What could they watch from the turret wall?
Answer:
They could watch the mowers from the turret wall.

b. Our gates were strong, our walls were thick,
so smooth and high no man could win.

i. How safe was The Castle?
Answer:
The Castle was safe with thick and high walls and strong gates.

ii. What was the firm belief of the soldiers?
Answer:
The firm belief of the soldiers was that none on earth could win it.

c. A foothold there, no clever trick
could take us dead or quick,
only a bird could have got in.

i. What was challenging?
Answer:
Entering The Castle was a challenging task.

ii. Which aspect of The Castle’s strength is conveyed by the above line?
Answer:
No one could enter but the birds could enter. This seems The Castle is too high and strong enough for anyone to enter.

d. ‘Oh then our maze of tunneled stone
Grew thin and treacherous as air.
The Castle was lost without a groan,
The famous citadel has overthrown.

i. Bring out the contrast in the first two lines.
Answer:
Once The Castle was very strong and thick, now it became helpless and thin because of the greedy disloyal warder.

ii. What happened to The Castle?
Answer:
The Castle was captured by the enemies for disloyalty.

e. ‘we could do nothing, being sold.’

i. Why couldn’t they do anything?
Answer:
They couldn’t do anything because they were betrayed by one of the soldiers.

ii. Why did they feel helpless?
Answer:
They felt helpless because they were surrounded by enemies in an unexpected way with the help of their own greedy disloyal warder.

Additional Questions:

a. ‘For what, we thought, had we to fear
with our arms and provender, load and load.

i. Do they have fear?
Answer:
No, they don’t have any fear.

ii. What does ‘our arms’ mean?
Answer:
Our arms’ means powerful weapons.

b. A foothold there, no clever trick
Could take us dead or quick,
Only a bird could have got in.

i. Who does ‘us’ refer to?
Answer:
‘Us’ refers to soldiers who are in The Castle.

ii. What does ‘quick’ mean here?
Answer:
Here ‘quick’ means alive.

c. Our captain was brave and we were true.
There was a little private gate,
A little wicked wicket gate,
The wizened warder let them through.

i. Who does ‘we’ refer to?
Answer:
‘We’ refer to soldiers.

ii. Whose captain was brave?
Answer:
The loyal soldier’s captain was brave.

iii. Who guarded the wicket-gate?
Answer:
The wicket gate was guarded by a wicked guard.

d. Grew thin and treacherous as air.
The cause was lost without a groan,
The famous citadel overthrew,

i. How did the strong castle become?
Answer:
The strong castle became thin and treacherous.

ii. What does ‘overthrown’ mean?
Answer:
‘Overthrown’ means defeated. The soldiers were defeated by the enemies.

e. ‘How can this shameful tale be told?
I will maintain until my death

i. Does the narrator say about his failure as a shameful tale?
Answer:
Yes, the narrator says about his failure as a shameful tale.

ii. What will be maintained until his death?
Answer:
The narrator decided not to disclose this shameful story to anyone. This will be maintained until his death.

5. Explain the following lines with reference to the context: (Text Book Page No. 22)

a. They seemed no threat to us at all.
Reference:
This line is taken from the Poem – “The Castle”, Poet – “Edwin Muir”.
Context:
Here the poet talks about the power of The Castle.
Explanation:
The soldiers of The Castle were confident of their castle’s physical strength. Through the turrets, they were able to watch the mowers and no enemy was found up to a distance of half a kilometer and so they seemed no threat to The Castle.

b. How can this shameful tale be told?
Reference:
This line is taken from the Poem – “The Castle”, Poet – “Edwin Muir”.
Context:
Here the poet talks about the unexpected failure of the soldiers.
Explanation:
The soldiers believed that The Castle was absolutely safe because their captain was brave and the soldiers were loyal. Yet these men are defeated by the enemies. The enemies got help from one of their own warders, who lets the enemy soldiers through a little gate.

c. ‘I will maintain until my death’
Reference:
This line is taken from the Poem – “The Castle”, Poet – “Edwin Muir”.
Context:
Here the poet talks about the ‘shameful act’.
Explanation:
The narrator decided not to disclose this shameful story (soldiers got failure because of the greedy disloyal warder) to anyone. This will be maintained until his death.

d. Our only enemy was gold
Reference:
This line is taken from the Poem – “The Castle”, Poet – “Edwin Muir”.
Context:
Here the poet talks about the ‘success of the enemy’.
Explanation:
The narrator wondered about the tricks played by enemies. At last, the enemy won them by giving them gold as a bribe. So the narrator called the enemy gold.

6. Read the poem and complete the table with suitable rhyming words: (Text Book Page No. 22)

Question 1.

Answer:

7. Underline the alliterated words in the following lines: (Text Book Page No. 22)

1. With our arms and provender, load on load
2. A little wicked wicket gate.
3. The wizened warder let them through.

8. Poetic Devices/Figure of speech:

Listening:

The Soldier:

If I should die, think only this of me:
That there’s some corner of a foreign field
That is forever England. There shall be
In that rich earth a richer dust concealed;
A dust whom England bore, shaped, made aware,
Gave, once, her flowers to love, her ways to roam;
A body of England’s, breathing English air,
Washed by the rivers, blest by suns of home.
And think, this heart, all evil shed away,
A pulse in the eternal mind, no less
Gives somewhere back the thoughts by England given;
Her sights and sounds; dreams happy as her day;
And laughter learned of friends and gentleness,
In hearts at peace, under an English heaven.
– Rupert Brooke

The Castle Summary in Tamil

கோடை முழுவதும் ஓய்வாய்
அந்த கோபுர உச்சியில் நின்று
எங்கள் விழிகள் புல்வெளிகளை நோக்கின.
எதிரிகளும் நோக்கினர் அரைமயில் தூரத்திலிருந்து.
எப்பக்கம் இருந்தும் அவர்கள் அச்சுறுத்துவதாய் இல்லை.

எதற்காக நாம் பயப்பட வேண்டும்
பணபலமும் படைபலமும் குவிந்திருக்கும் போது,
எமது படைக்கலன்கள் அடுக்கடுக்காய் உயர்ந்திருக்கும் போது,
நமத நட்பு நாடுகள் அருகிலிருக்கும் போது,
இலைகள் நிறைந்த மரங்கள் இந்த கோடை சாலை மீது இருக்கும் போது,

எமது வாயில்களும் வலியது, மதில்சுவர்களும் வலியது
மிக உயர்ந்தது, எவரும் வெற்றிகொள்ள இயலாது,
எந்தவொரு காலடியோ, கூர்மிகு சூழ்ச்சியோ எம்மை எளிதாய் நெருக்கிட முடியாது)
எந்நேரமும் நுழைந்திட பறவையால் மட்டுமே முடியும்.

கையூட்டாக எதைத் தரமுடியும் அவர்களால்?
தைரியமான தளபதி எமது நேர்மையான மனது எமது…….
இருந்தது ஒரு சிறிய மறைவான நுழைவாயில்,
சிறிய ஆபத்தான நுழைவாயில்,
வயதான வாயில்காவலன் அவர்களை உள்நுழைய அனுமதித்தான்.

ஓ! பின் எமது சிக்கலான கற்களால் ஆன சுரங்கக்குகை
மெல்லியதாய் துரோகம் நிறைந்ததாய் உயர்ந்தன.
காரணங்கள் கண்ணீர் துளிகள் இன்றி கடந்தன. ப
ுகழ்வாய்ந்த அரியனையோ சூறையாடப்பட்டது,
அதன் இரகசிய கிடங்குகளும் களவாடப்பட்டது.

எவ்வாறு கூறுவேன் இந்த இழிநிலை கதையை?
இரகசியம் காப்பேன் என்னுயிர் நீங்கும் வரை
ஏதும் செய்ய இயலவில்லை எங்களால், விற்கப்படும் போது
எமது ஒரே எதிரியாய் வந்தது பொன்,
எமது ஆயுதங்கள் அனைத்தும் அதன் முன் வீண்.

கவிஞரைப் பற்றி:

எட்வின் மீயூர் (Edwin Muir. 1887-1959) ஒரு புகழ் பெற்ற ஸ்காட்லாந்து (Scotland) நாட்டு புலவர் (poet., நாவல் ஆசிரியர் (Novelist, மொழிபெயர்ப்பாளர் (Translator), மற்றும் விமர்சகராவார் (Critic). இவர் தனது எளிய (vivid)பாடல்களால் நினைவு கூறப்படுபவர். இவர் தனது முதிய வயதில் (old age) பாடல்கள் எழுதத் தொடங்கினார். பின் தனது தனித்தன்மை வாய்ந்த தத்துவமுறை பாடல்களுக்கு தனது முதுமையில் அங்கிகாரம் பெற்றார்.

முதல் பாடல்கள்’ (First poem) மற்றும் ‘புதிதாய் இறந்தோரின் பாடல்கள்’ (Chorus of the Newly dead) இவை இரண்டும் மீயூரின் தொடக்க கால முயற்சியாகும். இவரின் பிந்தைய கவிதைத் தொகுப்பு ‘காலக் கூறு வித்தியாசங்கள், குறுகிய இடம்’, ‘கடல் பயணம்’ மற்றும் பல பாடல்களை உள்ளடக்கியது. ‘குழப்பம்’ மற்றும் ‘ஏதேனில் ஒரு கால்’ (one foot in Eden) போன்றவையும் அடங்கும்.

கவிதையைப் பற்றி:

“அரண்மனை” என்னும் இந்த கவிதை நன்முறையில் பாதுகாக்கப்பட்ட அரண்மனையை (castle) சிறைபிடித்ததைப் பற்றியும் அதில் உள்ள படைவீரர்களைப் (soldier) பற்றியும் வெளிப்படுத்துகிறது) படை வீரர்கள் தங்களின் உடல் வலிமையையும் பாதுகாப்பையும் பற்றி பெறுமைப்பட்டு வியந்தார்களே தவிர தாங்கள் வீழ்த்தப் படப்போவதைப் பற்றி யோசிக்கவில்லை.

கோட்டையின் பின்புறம் ஒரு இரகசியக் கதவு இருந்தது. அக்கதவின் காவலாளி எதிரிகளால் பணம் கொடுத்து வாங்கப்பட்டான். எதிரிகள் கோட்டைக்குள் புகுந்து தாக்கி சேதப்படுத்தினர். கவலையை மறந்து இருக்கும் படைவீரர்களின் வாழ்வில் எதிர்பாராத போரை சந்திக்கும் இக்கவிதையைப் பற்றி தெளிவாக காண்போம்.c

Tamilnadu State Board New Syllabus Samacheer Kalvi 9th Science Guide Pdf Chapter 3 Fluids Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 9th Science Solutions Chapter 3 Fluids

9th Science Guide Fluids Text Book Back Questions and Answers

I. Choose the correct answer:

Question 1.
The size of an air bubble rising up in the water
(a) decreases
(b) increases
(c) remains the same
(d) may increase or decrease
Answer:
(b) increases

Question 2.
Clouds float in the atmosphere because of their low
(a) density
(b) pressure
(c) velocity
(d) mass
Answer:
(a) density

Question 3.
In a pressure cooker, the food is cooked faster because
(a) increased pressure lowers the boiling point.
(b) increased pressure raises the boiling point.
(c) decreased pressure raises the boiling point.
(d) increased pressure lowers the melting point.
Answer:
(b) increased pressure raises the boiling point

Question 4.
An empty plastic bottle closed with an airtight stopper is pushed down into a bucket filled with water. As the bottle is pushed down, there is an increasing force on the bottom. This is because
(a) more volume of liquid is displaced.
(b) more weight of liquid is displaced.
(c) pressure increases with depth.
(d) All the above.
Answer:
(c) pressure increases with depth

II. Fill in the blanks :

1. The weight of the body immersed in a liquid appears to be ………………… than its actual weight
Answer:
less

2. The instrument used to measure atmospheric pressure is …………
Answer:
Barometer

3. The magnitude of buoyant force acting on an object immersed in a liquid depends on ……………. of the liquid.
Answer:
density

4. A drinking straw works on the existence of ……………….
Answer:
atmospheric pressure

III. State whether true or false. If false, correct the statement:

1. The weight of fluid displaced determines the buoyant force on an object.
Answer:
True.

2. The shape of an object helps to determine whether the object will float or not.
Answer:
False.
Correct statement: The density of an object helps to determine whether the object will floater sink.

3. The foundations of high-rise buildings are kept wide so that they may exert more pressure on the ground.
Answer:
False.
Correct statement: They may exert less pressure on the ground.

4. Archimedes’ principle can also be applied to gases.
Answer:
True.

5. Hydraulic press is used in the extraction of oil from oilseeds.
Answer:
True.

IV. Match the following :

Answer:

V. Answer in brief :

Question 1.
On what factors the pressure exerted by the liquid depends on?
Answer:
The pressure exerted by the liquid depends on the

• Depth
• Density of the liquid
• Acceleration due to gravity.

Question 2.
Why does a helium balloon float in the air?
Answer:
Helium is much less dense than ordinary air which gives them buoyancy and thus floats in the air.

Question 3.
Why it is easy to swim in river water than in seawater?
Answer:
The question itself is wrong. It is easier to swim in seawater than in the river water. It is because seawater has
(i) greater density and
(ii) larger buoyant force than river water.

Question 4.
What is meant by atmospheric pressure?
Answer:
The pressure exerted by the atmospheric gases on its surroundings and on the surface of the earth is called atmospheric pressure.

Question 5.
State Pascal’s law.
Answer:
Pascal’s law: The external pressure applied to an incompressible liquid is transmitted uniformly throughout the liquid.

VI. Answer in detail:

Question 1.
An appropriate illustration proves that the force acting on a smaller area exerts a greater pressure.
Answer:
Consider standing on loose sand. Your feet go deep into the sand. Now, when you lie down on the sand, you will find that your body will not go that deep into the sand. In both cases, the force exerted on the sand is the weight of your body which is the same. This force acting perpendicular to the surface is called thrust. When you stand on loose sand, the force is acting on an area equal to the area of your feet.

When you lie down, the same force acts on an area of your whole body, which is larger than the area of your feet. Therefore the effect of thrust, that is, the pressure depends on the area on which it acts. The effect of thrust on sand is larger while ‘ standing than lying.

Question 2.
Describe the construction and working of the mercury barometer.
Answer:

Mercury Barometer
1. It is designed by Torricelli.

Construction :
2. Mercury Barometer consists of long glass tube closed at one end and opened at the other.
3. Mercury filled through open end and close that end by thumb and open it after immersing it into a trough of mercury.

Working:
4. The Barometer works by balancing the mercury in the glass tube against the outside air pressure.
5. If air pressure increases, it pushes more of the mercury up into the tub.
6. If air pressure decreases, more mercury drains from the tub.
7. As vacuum cannot exert pressure, Mercury in the tube provides a precise measure of air pressure which is called atmospheric pressure.
8. It is used in a laboratory or weather station.

Question 3.
How does an object’s density determine whether the object will sink or float in water?
Answer:
Whether an object will sink or float in a liquid is determined by the density of the object compared to the density of the liquid. If the density of a substance is less than the density of the liquid it will float. For example, a piece of wood which is less dense than water will float on it. Any substance having more density than water (for example, a stone), will sink into the water.

Question 4.
Explain the construction and working of a hydrometer with a diagram.
Answer:

Purpose:
To measure density (or) relative density of the liquid.

Principle :
The weight of the liquid displaced by the immersed portion of the hydrometer is equal to the weight of the hydrometer. [Flotation principle].

Construction
Lower end of hydrometer :
A cylindrical stem having a spherical bulb which partially W Lead shots
filled with lead shots or mercury which helps to float or stand vertical in liquids.

Upper end of hydrometer:
A narrow tube has markings so that the relative density of liquids can be read off directly.

Working:

1. Liquid to be tested is poured into the glass jar.
2. The hydrometer is gently lowered into the liquid until it floats freely.
3. The reading against the level touching the tube gives the relative density of the liquid.

Question 5.
State the laws of flotation.
Answer:
Laws of flotation are

• The weight of a floating body in a fluid is equal to the weight of the fluid displaced by the body.
• The centre of gravity of the floating body and the centre of buoyancy are in the same vertical line.

VII. Assertion and Reason :

Mark the correct answer is:
(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c ) If assertion is true but reason is false.
(d) If assertion is false but reason is true.

Question 1.
Assertion (A) : To float, body must displace liquid whose weight is equal to the actual weight.
Reason (R): The body will experience no net downward force in that case.
Answer:
(a) Both assertion and reason are true and reason is the correct explanation of assertion]

Question 2.
Assertion (A) : Pascal’s law is the working principle of a hydraulic lift.
Reason (R): Pressure is thrust per unit area.
Answer:
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.]
Reason : Pascal’s law is the working principle of Hydraulic lift. In Hydraulic lift, applied pressure is transmitted uniformly and multiplied throughout the system.

VIII. Numerical Problems :

Question 1.
A block of wood of weight 200 g floats on the surface of water. If the volume of the block is 300 cm3, calculate the upthrust due to water.
Answer:
Weight of woodblock, m = 200 g
Volume of the woodblock, V = 300cm³
Upthrust = Weight of the fluid displaced = Volume of the woodblock
Upthrust = 300 cm³

Question 2.
Density of mercury is 13600 kg m^-3. Calculate the relative density.
Answer:
Density of Mercury = 13600 kg m^-3
Density of water at 4°C= 1000 kg m^-3

Question 3.
The density of water is 1 g cm^-3. What is its density in S.I. units?
Answer:
Density of water in SI units = 1000 kg / m³

Question 4.
Calculate the apparent weight of wood floating on water if it weighs 100g in air.
Answer:
Mass of wood = 100 g.
As the wood floats on the water, water will not be displaced.
So, the actual weight of wood is equal to the Apparent weight of wood.

IX. Higher Order Thinking Skills :

Question 1.
How high does the mercury barometer stand on a day when atmospheric pressure is 98.6 kPa?
Answer:
Pressure of Atmosphere PatnT = 98.6 kPa.
Density of Mercury, ρ_Hg = 13.6 × 10³ kg/cm³
Acceleration due to gravity, g = 9.8 m/s²

Question 2.
How does a fish manage to rise up and move down in the water?
Answer:

• Fish manages to rise up in the water by reducing its density by filling oxygen in the bladder via the gills. Thus volume will be increased to support its ascending motion.
• Fish moves down by decreasing its volume by releasing oxygen from the bladder. Thus volume will be decreased so it will sink in the water.

Question 3.
If you put one ice cube in a glass of water and another in a glass of alcohol, what would you observe? Explain your observations.
Answer:
Ice cube in water: As the density of ice cube is less than water, the ice cube floats in water.
Ice cube in alcohol: As the density of the ice cube is greater than alcohol, the ice cube will sink in alcohol.
Note: Density : Water = 1.00, Ice cube = 0.917, Alcohol = 0.78

Question 4.
Why does a boat with a hole in the bottom would eventually sink?
Answer:
A boat with a hole in the bottom eventually sinks due to :

• The water entered through a hole will increase the weight of the boat.
• The boat becomes heavier so it cannot displace more water. So the boat sinks.

Intex activities

ACTIVITY – 1

Stand on the loose stand. Your feet go deep into the sand. Now, lie down on the sand. What happens? You will find that your body will not go that deep into the sand. Why?

Aim:
To demonstrate the effect of thrust

Materials Required:
Sand

Procedure:

1. 1. First, you stand on the sand on your feet.
   2. Lie down on the sand with your whole body.

Observation:

1. While standing on your feet on sand, your feet go deep into the sand.
2. While lying down with your body on the sand, your body will not go deep into the sand.

Conclusion:

1. Pressure depends upon the area on which it acts.
2. The effect of thrust on sand is larger while standing than lying.

ACTIVITY – 2

Take a transparent plastic pipe. Also, take a balloon and tie it tightly over one end of the plastic pipe. Pour some water in the pipe from the top. What happens? The balloon tied at the bottom stretches and bulges out. It shows that the water poured in the pipe exerts pressure on the bottom of its container.

Aim: To demonstrate that water exerts pressure on the bottom of the container.

Materials Required: Plastic pipe, Balloon, Water.

Procedure :

1. Take a transparent plastic pipe and a balloon.
2. Tie the balloon tightly over one end of the plastic pipe.
3. Keep the pipe with the closed end at the bottom.
4. Pour some water in the pipe from the top.

Observation: The balloon tied at the bottom stretches and bulges out.

Conclusion: Water poured in the pipe exerts pressure on the bottom of its container.

[End of the activity]

ACTIVITY-3

Take a large plastic can. Punch holes with a nail in a vertical line on the side of the can as shown in the figure. Then fill the can with water. The water may just dribble out from the top hole, but with the increased speed at the bottom holes as depth causes the water to squirt out with more pressure.

Aim:
To demonstrate that pressure increases as depth increases.

Materials Required:

1. Large plastic can.
2. A sharp nail.

Procedure :

1. Take a large plastic can.
2. Punch holes with a nail in a vertical line up on the side of the can every inch or several centimeters.

Observation:

1. Water dribbles out from the top hole.
2. Water from the bottom hole flows with increased speed.

Conclusion:
Depth causes water to squirt out with more pressure.

ACTIVITY – 4

Take two liquids of different densities say water and oil to the same level in two plastic containers. Make holes in the two containers at the same level. What do you see? It can be seen that water is squirting out with more pressure than oil. This indicates that pressure depends on density of the liquid.

Aim :
To demonstrate pressure depends on the density of the liquid.

Materials Required:

1. Two plastic containers
2. Water
3. Oil (Both same volume)
4. Sharp nail

Procedure:

1. Take water and oil to the same level in two plastic containers.
2. Make a hole at the same level in two containers.

Observation:
Water squirts out with more pressure than that of oil.

Conclusion:
Pressure depends on the density of the liquid.

ACTIVITY – 5

Take two identical flasks and fill one flask with water to the 250 cm³ mark and the other with kerosene to the same 250 cm³ mark. Measure them in a balance. The flask filled with water will be heavier than the one filled with kerosene. Why? The answer is in finding the mass per unit volume of kerosene and water in respective flasks.

Aim :
To prove that the density of a substance is the mass per unit volume of a given substance.

Materials Required:

1. Two identical flasks.
2. Water
3. Kerosene (same volume as water)

Procedure :

1. Take two identical flasks.
2. Fill one flask with water to 250 cm³ mark.
3. Fill the other flask with kerosene to the same 250 cm³ mark.
4. Measure both flasks in balance separately.

Observation :
The flask filled with water will be heavier than that of the flask filled with kerosene.

Conclusion :

1. In the above activity, we know that Both water and kerosene have same volume (i.e.) 250 cm³.
2. The density of the water lg / cm³ and density of kerosene is 0.8g / cm³ mass
3. Density = \(\frac{\text { mass }}{\text { volume }}\), therefore mass = Density x volume
   Hence mass of water = 1g/cm³ x 250 cm³ = 250g
   mass of kerosene = 0.8 g / cm³ x 250 cm³ = 200g
4. Even though, water and kerosene have same volume, they have different densities. So water and kerosene have different masses.
5. Water has more mass than kerosene.
   Hence, we proved that the density of the substance is the mass per unit volume of the substance. [End of the activity]

9th Science Guide Fluids Additional Important Questions and Answers

I. Choose the correct answer :

Question 1.
Intermolecular forces are stronger in ………………
(a) gases
(b) liquids
(c) solids
(d) all the above
Answer:
(c) solids

Question 2.
Water (or) liquids exert pressure on
(a) Upward direction
(b) Downward direction
(c) Lateral direction
(d) All the above
Answer:
(d) All the above

Question 3.
The pressure does not depend upon
(a) Depth
(b) Area
(c) Density
(d) Acceleration due to gravity
Answer:
(b) Area

Question 4.
Fluids in general are
(a) Gases
(b) liquids
(c) Gases or Liquids
(d) None of these
Answer:
(c) Gases or Liquids

Question 5.
Scuba divers wear special suits to withstand
(a) Low pressure
(b) High pressure
(c) Low temperature
(d) High temperature
Answer:
(b) High pressure

Question 6.
To find out relative density of the substance, with respect to density of water……………C is taken.
(a) 4°
(b) 0°
(c) 100°
(d) 60°
Answer:
(a) 4°

Question 7.
Density Bottle is also called as
(a) Saccharometer
(b) Lactometer
(c) Pycnometer
(d) Barometer
Answer:
(c) Pycnometer

Question 8.
An object completely immersed in fluid displaces its own volume of fluid.
(a) Floatation principle
(b) Principle of buoyancy
(c) Pascal’s law
(d) Archimedes principle
Answer:
(d) Archimedes principle

Question 9.
A solid floats in liquid with a portion of it being submerged. Then
(a) The liquid exerts an upthrust equal to weight of the solid
(b) The weight of the dispersed liquid is equal to the weight of solid
(c) Solid exerts a force equal to its weight on liquid
Choose correct statements
(A) a & b
(B) a & c
(C) b & c
(D) All of these
Answer:
(A) a & b

Question 10.
The principle of “Hydrostatic balance” was devised by
(a) Torricelli
(b) Pascal
(c) Archimedes
(d) Newton
Answer:
(c) Archimedes

Question 11.
Saccharometer is used to measure the density of …………….in a liquid.
(a) Milk
(b) Sugar
(c) Alcohol
(d) Ether
Answer:
(b) Sugar

Question 12.
Most buoyant objects are those with relatively
(a) high volume
(b) higher mass
(c) low density
(d) less viscosity
(A) a & b (B) a & c (C) b & c (D) b&d
Answer:
(B) a & c

Question 13.
If there were no gravity, which of the following will not be there for fluid? (HOTS)
(a) Viscosity
(b) Density
(c) Pressure
(d) upthrust
Answer:
(d) upthrust

Question 14.
Human lung is well adopted to breath at a pressure of ………….kPa.
(a) 106.7
(b) 101.3
(c) 98.4
(d) 33.7
Answer:
(b) 101.3

Question 15.
Petroleum-based products float on the surface of the water. This is due to their low ………….
(a) volume
(b) density
(c) specific gravity
(d) viscosity
(A) a & b (B) a & c (C) a & d (D) b & c
Answer:
(D) b & c

II. Fill in the blanks :

1. It is easy to compress a gas whereas liquids are ………………….
Answer:
Incompressible

2. The net force in a particular direction is called ………………….
Answer:
Thrust

3. All flowing substances, both liquids, and gases are called ………………….
Answer:
Fluids

4. The air pressure at sea level is referred as ………………….
Answer:
Atmospheric pressure

5. The pressure in mines is ………………….than sea level.
Answer:
Greater

6. ………………….is the instrument used to measure the atmospheric pressure.
Answer:
Barometer

7. On each lm2 of surface, the force acting is ………………….
Answer:
1.013 kN

8. ………………….is a device for measuring atmospheric pressure without the use of liquids.
Answer:
Aneroid Barometer

9. Absolute Pressure is zero-referenced against a ………………….
Answer:
Perfect Vaccum

10. Psi stands for ………………….
Answer:
Pascal per inch

11. A tyre pressure of 30psi is almost ………………….the atmospheric pressure.
Answer:
Twice

12. The density of the substance is the …………………. of a given substance.
Answer:
mass per unit volume

13. Hydrometer is based on the principle of ………………….
Answer:
Flotation

14. The upward force that is caused due to the pressure difference in liquid (or fluid) is called ………………….
Answer:
Buoyant force

15. Hot air is ………………….dense than ordinary air.
Answer:
less

16. The Lactometer works on the principle of ………………….of milk.
Answer:
gravity

17. Icebergs and ships stay afloat due to ………………….
Answer:
Buoyancy

18. Archimedes principle is the consequence of ………………….
Answer:
Pascal’s law

19. The point in which the force of buoyancy is supposed to act is known as …………………..
Answer:
Centre of buoyancy

20. The centre of gravity of the floating body and the centre of buoyance are in the same ………………….line.
Answer:
Vertical

21. In a fluid, buoyant force exists because the pressure at the ………………….of an object is greater than the pressure at the top.
Answer:
bottom

III. Match the following :

(I)

Answer:
1. d
2. c
3. b
4. a

(II)

Answer:
1. c
2. d
3. a
4. b

IV. State whether true or false. If false, correct the statement:

1. The shape and size of the solids do not easily change.
Answer:
True.

2. Liquid exerts pressure in the upward direction.
Answer:
False.
Correct statement: Liquid exerts pressure in all directions.

3. The barometer works by balancing the Mercury in the glass tube along with the outside air pressure.
Answer:
False.
Correct statement: The barometer works by balancing the Mercury in the glass tube against the outside air pressure.

4. The absolute pressure is zero-referenced against atmospheric pressure.
Answer:
False.

Correct statement: The absolute pressure is zero-referenced against a perfect vacuum.

5. The external pressure applied on an incompressible liquid is transmitted uniformly throughout the liquid.
Answer:
True.

6. The correct lactometer reading is only obtained at a temperature of 60° C.
Answer:
True.

7. If the buoyant force is less, the object will float.
Answer:
False.
Correct statement: If the buoyant force is less, the object will sink.

8. If the volume of object is above the water surface, then the object is less densed.
Answer:
True.

9. Upthrust = weight of the fluid displaced – apparent weight of the object.
Answer:
False.
Correct statement: Upthrust = Weight of the fluid displaced – apparent loss of weight of the object.

10. Salt water provides less buoyant force than freshwater.
Answer:
False.
Correct statement: Salt water provides more buoyant force than freshwater.

V. Very Short Answer Questions :

Question 1.
Differentiate Liquid from Gas.
Answer:
It is easy to compress a Gas. The liquid is Incompressible.

Question 2.
What is the SI unit of pressure?
Answer:
Newton per squaremeter (Nm^-2).

Question 3.
What are factors determining liquid pressure?
Answer:
(i) Depth (b) (ii) Density bf Liquid (□) (iii) Acceleration due to gravity (g).

Question 4.
Write the equation for pressure due to liquid column.
Answer:
P = hg ; P – Pressure, h- depth, p- density, g – Acceleration due to gravity.

Question 5.
What is referred to as atmospheric pressure?
Answer:
Air pressure at sea level is referred to as atmospheric pressure.

Question 6.
Expand the abbreviation ‘psi’.
Answer:
Psi = Pascal per inch.

Question 7.
What are Force multipliers?
Answer:
Hydraulic systems are known as-force multipliers.

Question 8.
Write the SI unit & symbol for density?
Answer:
SI unit = kilogram per meter cube (kg / m³).
Symbol = rho (ρ).

Question 9.
Where do we use lactometers?
Answer:
In milk processing units and Dairies.

VI. Answer in brief :

Question 1.
What happens when pressure is increased in solids?
Answer:
If the pressure is increased in solids

• it experiences tension
• it ultimately deforms (or) breaks.

Question 2.
How will you calculate fluid pressure?
Answer:

Question 3.
How will you find the absolute pressure?
Answer:

1. For pressures higher than atmospheric pressure:
   Absolute pressure = Atmospheric pressure + Gauge pressure.
2. For pressures lower than atmospheric pressure:
   Absolute pressure = Atmospheric pressure – Gauge pressure.

Question 4.
Why do Scuba divers wear special suits and equipment?
Answer:

1. Deep-sea has pressure twice that of atmospheric pressure.
2. At high pressure, parts of our body including blood vessels & soft tissues cannot withstand it.
   Hence they use special suits & equipment for protection.

Question 5.
Define Relative Density.
Answer:
Relative density of a substance is defined as ratio of density of substance to density of water at 4°C.

Question 6.
Name different types of Hydrometers with their applications.
Answer:

Question 7.
What do you understand by the term “Buoyancy”.
Answer:
When a body partially or completely immersed in a liquid (fluid), the pressure is more at the bottom and less at the surface in the liquid.
This Pressure difference causes an upward force called “Buoyant force”. The phenomenon is called ‘Buoyancy’.

Question 8.
How do submarines sink and float in water?
Answer:
Submarines change the level of floating by pumping in and pumping out water into its compartments.

Question 9.
Differentiate positive & negative buoyant.
Answer:
Positive Buoyant

1. Weight of the object is less than the amount of water displaced.
2. More buoyant force
3. Object will float

Negative Buoyant :

1. Weight of the object is more than the amount of water displaced.
2. Less Buoyant force.
3. Object will sink.

Question 10.
You have a bag of cotton and an iron bar, each indicating a mass of 100 kg when measured on a weighing machine. In reality, one is heavier than the other. Can you say which one is heavier and why?
Answer:
The bag containing the iron bar is heavier than cotton.
Reason: Although both of them have the same weight, the bag of the iron bar has less volume so more dense compared to the bag of cotton which has more volume and less dense.

VII. Answer in detail :

Question 1.
Derive an expression for Pressure due to the Liquid column.
Answer:
A tall beaker filled with water to form a liquid column
Area of the cross-section at bottom = A
Height of liquid column = h
The density of the liquid = ρ
Thrust at bottom of liquid column (F) = Weight of liquid.
F = mg …(1) (∵ m – mass of liquid)
Mass,m = ρ × V ……………… (2)
Volume of liquid columñ, V = Area of cross-section (A) × height (h)
V = Ah ………….(3)
Substitute (3) in (2) n, = ρ Ah ………………… (4)
Substitute (4) in (1) F = ρ Ahg ……………….(5)
Pressure (P) = \(\frac{\text { Thrust (F) }}{\text { Area (A) }}=\frac{\rho \text { A h g }}{\mathrm{A}}\)
∴ P = hpg – This is the expression for pressure due to the liquid column.

Question 2.
Describe the construction and working of the Pycnometer.
Answer:
Pycnometer (Density Bottle)

Purpose: To measure relative density.

Construction :

1. Pycnometer consists of a ground glass stopper with a fine hole through it.
2. When the bottle is filled and the stopper is inserted, the excess liquid rises through the hole and runs down outside the bottle.

Working:

1. The bottle will always contain the same volume of liquid at a constant temperature.
2. The density of the given volume of substance to the density of equal volume of referred substance is called relative density or specific gravity of the substance.

Question 3.
Explain the Archimedes principle with an example.
Answer:
Principle:
A body immersed in a fluid experiences a vertical upward buoyant force equal to the fluid it displaces.

Explanation:
(1) When a body is partially or completely immersed in a fluid at rest, it experiences an upthrust which is equal to the weight of the fluid displaced by it.

(2) Due to the upthrust, the body loses a part of its weight equal to upthrust.
Upthrust = Weight of the fluid displaced.
= Apparent loss of weight of the body.
Apparent weight of an object = True weight of object in air – upthrust.

Question 4.
Describe the purpose, principle and working of Lactometer.
Answer:
Purpose: Lactometer is an instrument to check the purity of milk.
Principle: Gravity of milk.

Construction :

1. Lactometer consists of a long graduated test tube with a cylindrical bulb.
2. The cylindrical bulb has graduation from 15 at the top and 45 at the bottom, which filled with mercury.
3. The test tube is filled with water.
4. The air chamber causes the instrument to float.
5. Mercury causes lactometer to sink up proper level and to float in an upright position in the milk.
6. There is a thermometer inside the lactometer that extends to the upper part of test tube.

Working:

1. The correct lactometer reading is only obtained at 60°C.
2. Lactometer measures the cream (density) content of milk.
3. Lactometer floats in milk if milk has more cream content.
4. The average reading of normal milk is 32.

VIII. Numerical Problems :

Question 1.
A vessel with water is placed on a weighing pan and it reads 600 g. Now a ball of mass 40 g and density is 0.80g / cm3 is sunk into the water with a pin of negligible volume as shown in the figure. The weighing pan will show the reading of …………….?

Solution :
Weight of vessel with water = 600g
Mass of ball = 40g
Density of bal = 0.80 g / cm³
Volume of the ball = \(\frac{\text { mass }}{\text { density }}=\frac{40}{0.80}\)= 50g
So, weight of vessel + volume of ball = 600 + 50 g
The weighing pan will show = 650g
The weighing pan will show = 650g
The reading of a spring balance when a block is suspended from it in air is 60 newton. This reading is changed to 40 newton when the block is submerged in water. Calculate the specific gravity of block.
60 – 40 = 20 newton Weight of block in air
Loss of weight in water 60-newton / 20 newton = 3

Question 2.
The reading of a spring balance when a block is suspended from it in air is 60 newton. This reading is changed to 40 newtons when the block ¡s submerged in water. Calculate the specific gravity of block.
Solution:
Weight of block in air = 60 newton
Loss of weight of block in water = 60 – 40 = 20 newton

The specific gravity of block = 3

Question 3.
The mass of a body ¡s 4 kg and its volume is 500 cm³. Find its relative density.
Solution:
Massofthebodym = 4kg = 4000g
Volume ofthebodyv = 500 cm³

Question 4.
Calculate the pressure produced by a force of 800 N acting on an area of 2.0 m²
Solution :
Force = 800 N
Area = 2.0m²
Pressure, P =\(\frac{\text { Force }}{\text { Area }}=\frac{800}{2.0}\) = 400 Nm^-2
Pressure P = 400 Nm^-2 (or) 400 Pa

Question 5.
A swimming pool of width 9.0 m and length 24.0 m is filled with water of depth 3.0 m. Calculate the pressure on the bottom of the pool due to the water.
Solution:
Width of the pool, b = 9.0 m
Length of the pool, h = 24.0 m
Depth ofthepool,h = 3.0m
Density of water, p 1000 kg/m³
Pressure due to column of Fluid, P = ρhg
Acceleration due to gravity, g = 9.8 m/s²
Substituting the values, P = ρhg
P = 100kgm^-3 × (3.0m) × (9.8ms^-2)
Pressure, P = 29400kgm^-1s^-2      ∵1Pa = 1kgm^-1s^-2
∴P = 29400 Nm^-2 (or) 29400Pa

Question 6.
A body of volume 100 cc is immersed completely in the weight of water and the jar before immersion of the weight of water and jar after immersion.
Answer:
Volume of body completely immersed in water, V = = 100cc
Weight of water and jar before Immersion = 700g
The volume of jar immersed in water = Volume of water displaced = 100cc
Density of water = 1g/cm³
Mass of water displaced = Apparent weight loss
Mass of water displaced = Volume × density
= 100cc × 1g/cm³
Apparent weight loss of body = 100 g
Weight of jar and water after immersion = Weight of water and jar before immersion – Apparent weight loss
= 700g – 100g
= 600g.

IX. Assertion and Reason :

(a) Mark the correct choice as:
(a) If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c) If assertion is true but reason is false.
(d) If assertion is false but reason is true.

Question 1.
Assertion (A) : The buoyant force on submerged rigid object can be considered to be acting at the centre of mass of object.
Reason (R) : In rigid body, force distributed uniformly through its volume can be considered to be acting at the centre of mass of the body.
Answer:
(c) Assertion is true but reason is false]
Reason : Centre of the mass of the body is fixed according to the distribution of density.

Question 2.
Assertion (A): The weight of the truck exerts less pressure on road.
Reason (R): The truck has six to eight wheels. As area increases pressure decreases.
Answer:
(a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion

Question 3.
Assertion (A): Air gets thinner with increasing altitude.
Reason (R): The atmospheric pressure increases as we go up in mountains.
Answer:
(c) Assertion is true but the reason is false
Reason: The atmospheric pressure decreases as we go up in mountains.

Question 4.
Assertion (A) : Lactometer is used to check the purity of milk.
Reason (R) : Lactometer measures the cream content of milk.
Answer:
(b) Both assertion and reason are true but the reason is not the correct explanation of the assertion
(b) Directions: In each of the following questions, a statement of Assertion (A) is given followed by a corresponding statement of Reason (R) just below it. Of the statements, mark the correct answer as :

Question 5.
Assertion (A) : The force acting on the surface of a liquid at rest, under gravity, in a container is always horizontal.
Reason (R) : The forces acting on a fluid at rest have to be normal to the surface.
Answer:
(d) Assertion is false but reason is true
Reason: The force acting on the surface of liquid at rest, under gravity, in a container is always perpendicular due to the fact that molecules at the surface is attracted by the molecules below the surface (i.e) an inward attraction.

Question 6.
Assertion (A): A sleeping mattress is so designed that when you lie on it, a large area of your body comes in its contact.
Reason (R) : This reduces the pressure on the body and sleeping becomes comfortable.
Answer:
(a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion]

Question 7.
Assertion (A): Wide wooden sleepers are kept below railway lines to reduce pressure on the railway tracks and prevent them from sinking in the ground.
Reason (R): Pressure is directly proportional to the area in which it is acting.
Answer:
(c) Assertion is true but the reason is false
Reason: Pressure is inversely proportional to the area in which it is acting.

X. Define the following

1. Define thrust: The force which produces compression is called thrust. Its S.I units is newton
2. Define pressure: Thrust acting normally to a unit area of a surface is called pressure. Its S.I. Unit is the pascal.
3. Define atmospheric pressure: The pressure exerted by the atmospheric gases on its surroundings and on the surface of the earth is called atmospheric pressure. 1 atm is the pressure exerted by a vertical column of mercury of 76 cm height.
4. Buoyant force: The upward force experienced by a body when partly or fully immersed in a fluid is called upthrust or buoyant force.
5. Pascal’s law: Pascal’s law states that an increase in pressure at any point inside a liquid at rest is transmitted equally and without any change, in all directions to every other point in the liquid.
6. Archimedes principle: Archimedes’ principle states that when a body is partially or wholly immersed in a fluid, it experiences an up thrust or apparent loss of weight, which is equal to the weight of the fluid displaced by the immersed part of the body.
7. Density: Density is known as mass per unit volume of a body. Its S.I. unit is kg nr5.
8. Relative density: Relative density is the ratio between the density of a substance and the density of water. The relative density of a body is a pure number and has no unit.
9. Hydrometer: A hydrometer is a device used to measure the relative density of liquids based on Archimedes’ principle.
10. Lactometer: Lactometer is a device used to check the purity of milk by measuring its density using Archimedes’principle.