Question

Friction is a necessary evil. Explain.

Answer 1

Friction affects the relative motion between two bodies in contact. Without friction, objects cannot move from a stationary position or stop when in motion. Suppose you are walking on the road and encounter a smooth surface. You will fall because there will be no friction to hold your feet firmly on the surface. Now, let us change the situation. Let us suppose you are standing on a smooth surface and you are asked to walk on that surface. Again, you will not be able to walk properly because of lack of friction. Hence, friction is a necessary evil.