Friction produces _________

Friction is a

Smooth surface produces _____ friction than a rough surface.

A small sphere falls from rest in a viscous liquid. Due to friction, heat is produced. Find the relation between the rate of produced heat and the radius of the sphere at terminal velocity.

A heavy box of mass 20 kg is placed on a horizontal surface . If coefficient of kinetic friction between the box and the horizontal surface . Is 0.25 calculate the force of kinetic friction Also calculate acceleration produced under a force of 98 N applied horizontally ?

In the following diagram a massless pulley is pulled by a constant force of magnitude P. There is no friction between the block and the floor. The acceleration produced in the block of mass m is

In the following figure, the pulley is massless and frictionless. There is no friction between the body and the floor. The acceleration produced in the body when it is displaced through a certain disatnace with force 'P' will be .