Chapter 9 class 8 friction science book work
Q–1 Fill in the blanks : 1. Friction opposes the motion between the surfaces in contact with each other. 2. Friction depends on the nature of surface. 3. Friction produces heat. 4. Sprinkling of powder on the carrom board reduces friction. 5. Sliding friction is lesser than the static friction. Q–2 Four children were asked to arrange forces due to rolling, static and sliding frictions in a decreasing order. Their arrangements are given below: a) Rolling, static, sliding b) Rolling, sliding, static c) Static, sliding, rolling d) Sliding, static, rolling Ans: Static, sliding, rolling Q–3 Amina runs her toy car on dry marble floor, wet marble floor, newspaper and towel spread on the floor. The force of friction acting on the car on different surfaces in increasing order will be: Options: a) Wet marble floor, dry marble floor, newspaper and towel b) Newspaper and towel, dry marble floor, wet marble floor c) Towel, newspaper, dry marble floor, wet marble floor d) Wet marble floor, dry ...