Notes of fibre to fabric chapter class 7
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Fibre to Fabric Class 7 Notes Science Chapter 3
April 23, 2019 by Sastry CBSE
CBSE Class 7 Science Notes Chapter 3 Fibre to Fabric Pdf free download is part of Class 7 Science Notes for Quick Revision. Here we have given NCERT Class 7 Science Notes Chapter 3 Fibre to Fabric.
CBSE Class 7 Science Notes Chapter 3 Fibre to Fabric
Fibres are very thin, thread-like strands from which fabrics (or cloths) are made. Some examples of fibres are cotton, wool, silk, flax, jute, nylon, polyester and polyacrylic. The fibres are spun into yarn (long continuous thread) which can then be woven on a loom to make a fabric (or cloth). Yam is a kind of long, twisted thread. Yarn is made from fibres by the process of spinning.
There are two types of fibres, i.e. natural fibre and man-made fibre (nylon, rayon). Some of our clothes are made from yarn derived from the animal fibre. These are the types of natural fibres as they are obtained from nature. Natural fibres are the fibres which are obtained from natural sources like plants and animals.
In Class VI, we have learnt about some fibres obtained from plants. In this chapter, we will study about some fibres obtained from animals. Wool and silk fibres are obtained from animals. Wool is obtained from the fleece (hair) of sheep or yak and silk fibres come from cocoons of the silk moth.
Wool
The wool comes from animals like sheep, goat, yak, camel, llama and alpaca. The wool yielding animals bear a thick coat of hair on their body. The hair which gives us wool and keeps them warm during the cold winter season. The hair (wool) on the body of wool-yielding animals trap a lot of air. Air spaces between the wool fibres trap air. Since the air is a poor conductor of heat. So, the air trapped in hair shields the body from cold and keeps them warm in winter.