Question

Explain why we call friction -a necessary evil.

Answer 1

We call Friction a necessary evil because we need it sometimes and in some cases we won't need it.
For example :- You need friction to stop yourself when you are running very fast.
And as you will be running with shoes , friction will try to oppose your motion but it cannot as force which you are applying is very much greater than frictional force , due to friction your shoe's sole will be getting damaged,
so in this case you would not want friction as it is damaging your shoe's sole.

Answer 2

Friction is usually called necessary evil. It means it is essential in life and we cannot do any work without it .

hope this may help u and be the brainliest friend ..