Question

"friction i a necessary evil" explain it with suitable example.

Answer 1

"Friction is a necessary evil" because friction occurs between the two surfaces which are in contact with each other. For example, when we push a heavy box kept on floor, the force of friction occurs between the surface of floor and the bottom of the box. And the care of a baby rolling on ground,friction occurs between the surface of ground and the surface of ball.In fact, friction acts on both the surfaces in contact with each other. Friction is a force which occurs when the two objects tend to side over each other and even when they are actually sliding (moving) over each other.

Answer 2

Friction is a necessary evil because friction is both useful and harmful.

For example, friction produces heat(which is a disadvantage) but at the same time, friction is used to light up a matchstick(which is an advantage)

For example, we slip of slippery roads(which is a disadvantage) but at the same time friction also helps us to walk(which is an advantage)