Ch3- Fibre to Fabric. 1. List some popular fabrics from which our clothes, curtains, carpets, bags and towels are made.

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Brian Hart
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1 Ch3- Fibre to Fabric Subjective type Very Short Answer Questions 1. List some popular fabrics from which our clothes, curtains, carpets, bags and towels are made. Cotton, wool, jute, silk, nylon, rayon, acrylic are some popular fabrics from which our clothes, curtains, carpets, bags and towels are made. 2. Is it possible to separate a yarn out of a piece of fabric? How? What does it mean? Yes, a loose yarn can be pulled out from edge of a piece of fabric. It means a fabric is made up of yarns arranged together. 3. What is a yarn made up of? Yarn is made up of thin strands called fibers spun together. 4. How do we obtain wool and silk? Wool is obtained from fleece of sheep or goat, hair of rabbits, yak and camel. Silk fibres is drawn from cocoons of silkworms. 5. From which parts of the plant cotton and jute are obtained?[ncert] Cotton is obtained from the fruits of the cotton plant, called cotton balls. Jute fibre is obtained from the stem of the jute plant. 6. Why are synthetic fibres becoming popular these days? Synthetic fibres are becoming popular these days because they are: Light in weight Durable Easily manufactured by chemicals Less expensive 7. Give some materials made from fibres on outer covering of coconut.

2 Or Name two items that are made from coconut fibre.[ncert] Jute bags, ropes and Foot mats. 8. Boojho with perfect eyesight was finding it difficult to pass thread through the eye of a needle. What can be the possible reason for this?[ncert Exemplar Problems] The end of the thread was separated into a few thin strands or the thread was quite thick can be the possible reasons. B. Short Answer Questions 1. When we look at any fabric, it seems like a continuous piece. But on looking closely, do our observations change? Explain. On looking closely to a piece of fabric, we observe that it consists of closely interlinked threads. These threads are closely woven together or knitted to form a fabric. 2. (a) What happens when you scratch the yarn along its length as shown below? The yarn splits up into thin strands called fibres. (b) Give one more example of a situation when you come across a similar observation. Individual answers 3. What are fibres? Where do the f ibres come from? The thin strands which constitute a yarn are called fibres. Fibres of fabrics such as cotton, jute, silk and wool are obtained from plants and animals. Fibres of fabric like nylon, rayon etc. are synthetic and made chemically. 4. Distinguish between natural and synthetic fibres with examples. Natural Fibres The fibres which are obtained from plant and animal sources are called natural fibres. Example: cotton, jute, silk Synthetic Fibres The fibres which are made from chemical substances are called synthetic fibres. Example: nylon, polyester, acrylic

3 5. You must have seen warrior dresses in museums as shown here. They were called 'Kavach'. What fibre do you think they wer e made from and why? Kavach dresses were made of thin fibres of metals such as iron that saves them from pointed weapons causing injuries during the war. 6. List few uses of cotton wool. Cotton wool is used to make wick for oil lamp, filling mattresses, quilts and pillows. 7. Explain how cotton wool is obtained. Cotton plants are grown at places having black soil and warm climate. The fruits of the cotton plant (cotton bolls) burst open and the seeds covered with cotton fibres are obtained. 8. List some states where cotton is grown. Throw light on their climate and soil type also. Punjab, Haryana, Rajasthan, Gujarat, Maharashtra, Madhya Pradesh, Andhra Pradesh, Tamil Nadu and Karnataka are some states where cotton is grown. Cotton plants are usually grown at places having black soil and warm climate. 9. Define spinning. How is it helpful in making yarn? The process of making yarn from fibres is called spinning. The fibres from a mass of cotton wool are drawn out and twisted with the help of a hand spindle or machine. This brings the fibres together and a yarn is formed. 10. Distinguish between weaving and knitting. Weaving Two sets of yarn are arranged together. It is done with handloom or powerloom. Knitting A single piece of yarn in used to make piece of fabric It is done by knitting machines or needles.

4 11. What would happen if you pull the yarn from a torn pair of socks? A single yarn gets pulled out continuously as the fabric gets unravelled. It is because they are made of knitted fabric. 12. What materials were used by people in ancient times for clothes? Unstitched clothes were used to wrap around the waist or legs. Lungi, dhoti and saree are commonly worn in India. 13.What material did people, who began to settle in agricultural communities, use to make clothes? Materials used in fabrics are vines, animal fleece or hair were used by people till they learnt to grow cotton or other fibre yielding plants. 14. Why did people drape fabrics around their bodies? How did stitching come into existence? Do we still wear any unstitched fabrics? Give examples. Stitching was not known in earlier times. So people draped fabrics around different parts of their body. The stitching of clothes began with the invention of sewing needles. Yes, we still wear unstitched fabrics such as saree, dhoti and turban. 15. India has been a major producer of cotton and its fabric. It even exports cotton fabric and items to many other countries. How does it help us? Export of fabric to other countries helps us to earn money. As fabric reaches more places, its demand even rises. This helps our country to earn more and more foreign money. 16. You have different yarns of cotton, silk, wool and polyester. If you hold them with tongs and burn them over a candle flame, what do you observe? How is burning of cotton similar to burning of paper?

5 Fabric Burning observations Smell on burning Cotton Does not shrink or melt Paper burning Silk Shrinks but not melts Burning hair Wool Shrinks but not melts Burning hair Polyester Shrinks and melts Plastic burning Burning of cotton is similar to burning of paper as they both are plant products.

3.1 VARIETY IN FABRICS

3.1 VARIETY IN FABRICS 3 Fibre to Fabric Paheli and Boojho won the first prize in a Science Quiz competition held at their school. They were very excited and decided to use the prize money to buy clothes for their parents. When