Question

what is frictional force.

Answer 1

it's a force which causes resistance in the path of the force applied first

or simply we can say opposite reaction on the other side ( action = reaction)

Answer 2

Friction is the force resisting the relative motion of solid surfaces , fluid layers , and materials elements sliding against each other. There are several types of Force And Frictional is also a type of Force ; Only becz. of this force we all are able to walk on surface , to write through pen & so more.
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