Question

Which of the following options illustrate the advantageous effects of friction?

• A. Wear and tear of shoes
• B. Walking
• C. Writing on blackboard with a chalk
• D. Fixing a nail to wall

Answer 1

Answer: (B), (C), (D)

The correct options are
B

Walking

C

Writing on blackboard with a chalk

D

Fixing a nail to wall

Friction is often called a necessary evil as it has both positive and negative effects. Some of the positive effects of friction are:

• It provides the necessary force for walking. It is very difficult to walk on a slippery surface.
• It helps us write on blackboard with a chalk. If friction was absent, chalk wouldn't remain stuck on the blackboard.
• It is because of friction that a nail remains fixed to the wall.

There are many other positive effects of friction as well. However, friction causing wear and tear of shoes is not desirable.