21. What are the characteristics of synthetic fibres?
(A) Dried up quickly and
(B) Less expensive and durable
(C) Readily available and easy to maintain
(D) All of the above
22. …………is an example of a plastic.
(A) Rubber
(B) Nylon
(C) Polythene
(D) Acrylic
23. The plastic which gets deformed easily on heating and can be bent easily are known as
(A) Thermosetting plastic
(B) Thermoplastics plastic
(C) Non-reactive plastic
(D) Reactive plastic
24. Which of the following is an example of thermoplastics?
(A) Polythene
(B) PVC
(C) Both (A) and (B)
(D) None of the above
25. The plastics which can be mould only once and can not be soften on heating are called
(A) Thermosetting plastics
(B) Thermoplastics
(C) Both (A) and (B)
(D) None of the above
26. Which of the following is an example of thermosetting plastics?
(A) Bakelite
(B) Melamine
(C) Both (A) and (B)
(D) None of the above
27. ……………..is a poor conductor of heat and electricity.
(A) Bakelite
(B) PVC
(C) Melamine
(D) All of the above
28. Melamine is used to make
(A) Floor tiles
(B) Kitchenware
(C) Both (A) and (B)
(D) None of the above
29. Bakelite is used for making
(A) Electrical switches
(B) Handles for utensils
(C) Both (A) and (B)
(D) None of the above
30. Plastic is a ……………..material.
(A) Non-reactive
(B) Reactive
(C) Rusting material
(D) None of the above
Answers:-
| 21- (D) | 22- (C) | 23-(B) | 24-(C) | 25-(A) | 26-(C) | 27-(A) | 28-(C) | 29-(C) | 30-(A) |