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SCIENCE CHAPTER 3 FIBRE TO FABRIC WORKBOOK ANSWER
Ch3. Fibre to fabrics
1. Name the following:
a) The fibre used for making gunny bags. –Jute fibre
b) The process of removal of wool from the sheep’s skin. -Shearing c) A spinning wheel made from wood. –Charkha
2. State whether the following statements are true or false. Correct the false statements.
a) The larva of silkworm feeds on strawberry leaves. False
The larva of silk worm feeds on mulberry leaves
b) The fibre is converted to yarn to make it thick, strong and long. True
c) A special clipper is used to remove hair from animals. True
d) Handlooms are large looms used in industries which are operated by electricity. False
Powerlooms are large looms used in industries which are operated by electricity.
3. Fill in the blanks:
a) Silk is a smooth, shiny, natural fabric obtained from animals.
b) Natural fibres are chemically improved to form synthetic fibres.
c) The invention of the needle helped in sewing pieces of fabrics together.
4. In the following questions, two statements are given- one labelled Assertion (A) and the other labelled Reason (R). Read the statements carefully and choose the correct alternative (A), (B), (C) and (D) as given below.
(A) Both A and R are true and R is correct explanation of the assertion. (B) Both A and R are true but R is not the correct explanation of the assertion.
(C) A is true but R is false.
(D) A is false but R is true.
Assertion: Cotton clothes keep us cool in warm weather.
Reason: Cotton fabric is naturally light and provides ventilation.
a)
ans: (A) Both A and R are true and R is correct explanation of the assertion.
b) Assertion: In India, jute is mainly grown in the states of Assam.
Reason: Jute plant grows well in the regions with low temperatures and less rainfall.
ans:
(C) A is true but R is false.
5. Define the following:
a) Picking of cotton
Ans: The process of collecting cotton from the bolls by hand is known as picking.
b) Retting
Ans: The stems of jute rot emitting a bad odour and the fibres are separated by hand by a process known as retting.
6. Differentiate between:
a) Natural fibres and Synthetic fibres
Ans: Natural fibres Synthetic fibres
7. Give reasons for the following:
a) Synthetic fibres are used to make a variety of fabrics.
Ans: ∙ Synthetic fibres have properties like heat resistance, resistance to most chemicals, low moisture absorbency and flame resistance which make them more useful.
∙ Hence they are used to make a variety of fabrics.
b) Silk is a popular luxury fibre.
Ans: ∙ Silk fabric is smooth and shiny.
∙ It became a popular luxury fibre because of its lustre and texture.
8. Creative type of question.
Texool Textile limited is a cottage industry. It provides job opportunities to villagers. This company believes in recycling its waste. The company provided Sulbha with waste cotton, wool and jute to create new products. Name some items that Sulbha can create from the waste.
Ans:
Cotton Reusable bags, Reusable cotton towels and napkins, Cutlery bags.
Jute Jute bags, Jute rope decorations, Waste baskets.
Wool Wool insulated lunch bag, Kitchen scrubbing pad, Decorations.
(Answers may vary, accept all relevant answers)
I. 9. Complete the given process of wool: (REFER TO TEXTBOOK)
10. Read the following paragraph and answer the following questions: Textile is a fabric that is knitted or woven and made from yarn. Thus, the textile industry is the industry responsible for taking a raw material, like cotton or wool, and spinning it into yarn that is later used to create a fabric. Developing, producing, manufacturing, and distributing textiles are the different processes included in this industry.
a) What do you mean by textile?
Ans: Textile is a fabric that's knitted or woven and made from yarn.
b) Which raw materials mentioned above are spun into yarn? Ans: Raw materials like cotton or wool spun into yarn.
11.Given below are four words. Each word has a name of a fabric hidden in it. Find the hidden fabrics. One example has been done for you.
12.
HOTS
a) Why we can’t weave cotton fibre directly into a fabric?
Ans: ∙ The cotton fibre is short, thin and fragile.
∙ As the fibre is thin and fragile, it cannot be woven directly into a fabric.
b) Why are cocoons boiled in water to obtain silk?
Ans: ∙ Silk thread is obtained from the saliva of silk worms. ∙ The larva of a silk worm feeds on mulberry leaves and secretes fine threads of silk.
∙ This silk is wrapped around the worm in a cocoon.
∙ Hence the cocoons are collected and boiled in water.
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6. Differentiate between:
a) Natural fibres and Synthetic fibres
Ans: Natural fibres Synthetic fibres
SCIENCE CHAPTER 3 FIBRE TO FABRIC NOTEBOOK WORK & TEXTUAL ANSWER
CHAPTER 3
FIBRE TO FABRIC
NOTEBOOK WORK
mind map ppt 10,11
process cotton, jute, wool
PROCESSING OF COTTON
PICKING
GINNING
SPINNING
WEAVING
processing of jute
The processing of wool involves the following four steps:
STEP 1 : Shearing - removal of wool from the sheep’s skin.
STEP 2: Grading - the fleece separated from the damaged wool.
STEP 3: Carding - passed through the rollers.
STEP 4: Spinning - Fibres twisted to make yarn.
Check Your Progress Pg 23
State the main difference between synthetic and natural fibres
• Give two examples each of synthetic and natural fibres.
Synthetic fibres- nylon, rayon, acrylic and polyester
Natural fibres- cotton, jute, hemp, coir, silk and wool
Check Your Progress Pg 25
What kind of soil is suitable for the growth of cotton plants?
Black fertile soil
• The fruits of the cotton plant are known as cotton bolls.
• Harvesting of jute plants is done at the harvesting stage.
Check your progress: 27
Explain the following process of obtaining wool from sheep – shearing and spinning.
Shearing is a process which includes the removal of wool from the sheep’s skin.
Spinning- Fibres are gathered together and drawn into a long rope and then twisted
to make yarn.
• Silk thread is obtained from the cocoons of silk worms.
Answers to the questions given in the Let’s Exercise
(QUESTION 1 TO 4 TO BE DONE IN TEXTBOOK
QUESTION 5 TO 9 IN FAIR NOTEBOOK)
Choose the correct option:
a. Which of the following fabrics is ideal for making summer clothing?
Ans: Cotton
b. Which of the following terms is used to describe cotton fruits?
Ans: Bolls
c. Which of the following are natural fibres?
Ans: Wool, silk, hemp
2. Fill in the blanks.
a. The basic unit of a fabric is a fibre.
b. Cotton needs black fertile soil with good moisture capacity.
c. Wool is obtained from the hair or the fleece of sheep.
d. The process of creating yarn from fibres is known as spinning.
3. State whether the following statements are True (T) or False (F).
a. Hemp is a synthetic fibre. False
b. The process of converting fibre to yarn is known as weaving. False
c. A takli is a device used for spinning yarn by hand. True
d. Synthetic fibres are prepared from chemical substances such as crude oil. True
4. Answer the following questions in one word or one sentence.
a. Name the process through which cotton is separated from the seeds. Ginning
b. What is yarn made up of? Yarn is made up of fibres.
c. Name the process of removal of wool from the sheep. Shearing
5. Answer the following questions in short.
a. Explain the process of spinning.
The process of creating yarn from fibres is known as spinning. In this process fibres are twisted to form a yarn.
b. How are synthetic fibres processed?
The chemical substances obtained from crude oil are heated and forced through very fine pores to obtain long, fine threads of synthetic fibres.
c. State the climatic conditions needed for the growth of cotton and jute plant.
Cotton plant grows well in warm climates and jute plant grows well in the regions
with high temperatures and heavy rainfall.
6. Give reasons.
a. Cotton clothes are used in summer.
Cotton fabric is naturally light and provides ventilation.
b. Wool is used to create different fabrics.
Wool can be blended with other fibres hence it is used to create different fabrics.
7. Answer the following questions in detail.
a. How are jute fibres converted into fabric?
The stems are immersed in water for few days and as they rot emitting a bad odour the fibres are separated by hand by a process known as retting. Later these fibres are converted into yarns to make fabric.
b. How are silk fibres collected?
Silk thread is obtained from the saliva of silk worms. The larva of a silk worm feeds on mulberry leaves and secretes fine threads of silk. This silk is wrapped around the worm in a cocoon. The cocoons are collected and boiled in water. The silk fibres are
then collected by hand.
8. HOTS (Higher Order Thinking Skills)
a. Why are jute fibres normally not used to make clothes?
The fabric made up of jute fibres is thick, coarse woven fabric. Hence it will not be
appropriate to wear clothes made up of coarse fabric.
b. Why are silk, rayon and nylon smooth to touch?
The fabric made up of silk rayon or nylon are having smooth and shiny texture and
hence smooth to touch.
9. Value based questions
There is a sign outside a supermarket. ‘Kindly use jute or cotton bags for shopping instead of
plastic bags.’ What could be the reason for this?
Plastic is non-biodegradable and pollutes the environment. Jute or cotton are natural
fibres and are biodegradable in nature. Hence it is recommended to use jute or cotton bags.