Define friction ? what is the cause of friction ? Give factors affection friction? Explain that friction is a necessary evil?
Answers
Define friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other.
What is the cause of friction
Causes of Friction:
Friction is a force that resists the relative motion between two objects or materials. The causes of this resistive force are molecular adhesion, surface roughness, and deformations.
Give factors affection friction
Friction depends partly on the smoothness of the contacting surfaces, a greater force being needed to move two surfaces past one another if they are rough than if they are smooth.
Explain that friction is a necessary evil?
Frictional force causes a lot of losses in general upkeep and wear and tear of machinery. Hence it is considered as a evil.