Explain why objects moving in fluids must have special shapes.

Important Questions on Friction

EASY

8th Punjab Board

IMPORTANT

Science>Chapter 12 - Friction>Exercises>Q 1

Friction opposes the _____ (motion / rest) between the surfaces in contact with each other.

EASY

8th Punjab Board

IMPORTANT

Science>Chapter 12 - Friction>Exercises>Q 1

Friction depends on the _____ (nature/volume) of surfaces.

EASY

8th Punjab Board

IMPORTANT

Science>Chapter 12 - Friction>Exercises>Q 1

Sprinkling of powder on the carrom board _____ (increases/reduces) friction.

EASY

8th Punjab Board

IMPORTANT

Science>Chapter 12 - Friction>Exercises>Q 2

Four children were asked to arrange forces due to rolling, static and sliding friction in decreasing order. Their arrangements are given below. Choose the correct arrangement.

EASY

8th Punjab Board

IMPORTANT

Science>Chapter 12 - Friction>Exercises>Q 3

Alida runs her toy car on a 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 _____.

MEDIUM

8th Punjab Board

IMPORTANT

Science>Chapter 12 - Friction>Exercises>Q 4

Suppose your writing desk is tilted a little. A book kept on it starts sliding down. Show the direction of the frictional force acting on it.

MEDIUM

8th Punjab Board

IMPORTANT

Science>Chapter 12 - Friction>Exercises>Q 5

You spill a bucket of soapy water on a marble floor accidentally. Would it make it easier or more difficult for you to walk on the floor? Why?

MEDIUM

8th Punjab Board