Page 128 - Viva ICSE Science 4 : E-book

E. Answer the following questions.

1. What is friction? Give a common example of friction from our daily life.

2. Give reasons.
(i) Friction slows down or completely stops any object from moving.

(ii) It is easier to walk on dry fl oor in comparison to wet fl oor.

3. Explain how we are able to write on a paper with a pencil.
4. Write about any fi ve uses of friction in our daily life.

5. Write about any four harmful eff ects of friction.

6. (i) Discuss some ways by which we can prevent friction.

(ii) Give some instances when we need to increase friction.

THINK AND ANSWER

1. Can force of friction work in the absence of gravitation?
2. If you let a cricket ball and a guava roll down a ramp, which one out of the two will
reach the ground faster? Give reason.

TALK ABOUT

Think of the instances when friction was harmful or useful to you, and share your experiences in the
class. Also, suggest ways to overcome the harmful eff ects of friction.

LINK AND LEARN

Make the model of a pair of shoes. Use thermocol sheet, clay, colourful ribbons, etc. to make your
pair of shoes. Do not forget to groove the soles for a better grip of the ground.

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