Question

12. Friction is not useful for us, why?
A. It causes wear and tear
B. Loss of energy
C. The heat produced during friction destroys the machine D. All of these
​

Answer 1

Answer:

D)All of these

Explanation:

The answer is all of these because it causes wear and tear, loss of energy and destroys the machine

Answer 2

Answer:

Friction is not useful for us because of The heat produced during friction destroys the machine

Explanation:

This is because when friction is produces more than required as a result the friction (energy) release in form of heat / some times fire