" 11.Friction is necessary evil,Explain."

Friction is a necessary evil. Explain.

Friction is a necessary evil. Explain.

Friction is a necessary evil. Explain.

Friction is a necessary evil.

"Friction is a necessary evil"-explain.

Friction is defined as the force which opposes the relative motion between two surfaces in contact. Friction is a necessary evil,explain.

Transpiration is necessary evil. Explain?