Question

Please answer the following questions.
C. Match the following.
1. Streamlined body. Opposes motion
2. Ball bearings Friction between ground & feet
3. Static friction Fish
4. Walking Snow on roads
5. Sand. Excessive heat
6. Machine parts. Grooves for grip
7. Tyres. Shafts of motors

D. Give reasons for the following.
1.Roller skates have ball bearings in the wheels.
2. It is slippery and difficult to walk on a floor with new tiles.

E. Answer the following.
1. Understanding rolling friction had lead to a revolution in the transport industry.
Comment.
2. Why are the soles of our shoes treaded?

Answer 1

D1. roller skates have Ball bearing in the wheels to increase the friction between the earth surface and the roller skates.

2. yes , it is difficult to to walk on the floor with new tiles because there is a lack of friction in-between the the legs and the tiles .

E 1. rolling friction plays a very important role in the revolution in the Transport . it is the backbone of the transport industry . the main part of transport is the circular wheels ..... and the friction in between the wheels and the surface .

2. the soles of our shoes are treaded because to increase the friction. the more the rough surface , the more friction ...

Answer 2

Answer:

Answer: for match the following

Match the following.

1. Streamlined body- Fish  

2. Ball bearings – Shafts of motors

3. Static friction – opposes motion

4. Walking – Friction between

ground and feet

5. Sand – Snow on roads

6. Machine parts – Shafts of motors

7. Tyres – Grooves for grip

Explanation:

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