synthetic fibres and Plastics Class 8 CBSE Practice questions(Short questions)

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Short questions
Question 1
Name any two blended fibres?
Answer
  Terry cot (terrylene+ cotton)
          Terry cot ( ferrylene+ wool)
Question 2
 Why is rayon called a regenerated fibres?
Answer
Rayon is called regenerated fibers because the original raw material cellulose is broken down and then reformed.
Question 3
Why is nylon considered to be a good material for making fishing nets?
Answer
Being a strong and lightweight material, it is used for making fishing net.
Question 4
Why electric plugs and switches are made of plastic?
Answer
Plastics are poor conductor of heat and electricity so electric plug and switches are made of plastic
Question 5
Why are plastic bottles commonly used to store chemicals in a chemistry laboratory?
Answer
Plastics have no reaction with water and air. They are non- reactive and do not corrode easily so they are used to store chemicals in chemistry laboratory.
Question 6
What can be used as a substitute for wool? Why?
Answer
Acrylic can be used as a substitute for wool because it is a lightweight, soft and warm synthetic fiber which is wrinkle- resistant, cheaper than wool and resistant to moths and chemicals.
Question 7
Distinguish between natural and synthetic fibers?
Answer
Natural fibers come from plants and animals such as cotton, jute etc.
Synthetic fibers are made from chemicals which come from wood, coal and petroleum such as rayon, nylon etc.

Question 8
Why nylon is used for making socks?
Answer
Nylon fiber show good frictional resistance. It is elastic in nature and highly durable so it is used for making socks.
Question 9
Why people prefer wearing cotton clothes over synthetic during summer?
Answer
Synthetic fibers cannot absorb moisture. This makes them unsuitable to be worn during summer when our body sweats.
Question 10
Why Polyester clothes should be avoided in kitchen?
Answer
Polyester is highly flammable so they should be avoided in kitchen.




Class 8 Maths Class 8 Science