Question

Explain why frictional force is said to be a contact force?

Answer 1

Hii Mate here is your Answer,

● What is a contact Force?

A force which can act only by physical connection is called Contact Force.

Like - Muscular Force and Friction

● Is Friction a contact Force? How?

Yes, Friction is a contact force because ot acts only by direct physical contact.

e.g. Ball stop moving due to direct friction with ground.

Breaks applied producing direct force on the Rims or the wheel.

Note : Friction always oppses the Motion and act an obstacle for it. It is harmful and useful also.

● Does Friction always in direct contact with the body?

Yes, In solids it is in direct contact even in fluids like liquid and gases also their particles are in direct contact of moving body.

☆☆☆HOPE THIS HELPS YOU A LOT ☆☆☆

Answer 2

frictional force is also called contact force because it always occur when two body rub against each other in other words it always occur when two body are rub against each other  for example you can take 1) when you rub you two hands 2) when you apply brakes 
hope his will help you