Question

name the force of friction that exists in ball bearing​

Answer 1

A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races.

Working principle for a ball bearing; red dots show direction of rotation.

A 4-point angular contact ball bearing

A ball bearing for skateboard wheels with a plastic cage

Wingquist's self-aligning ball bearing

The purpose of a ball bearing is to reduce rotational friction and support radial and axial loads. It achieves this by using at least two races to contain the balls and transmit the loads through the balls. In most applications, one race is stationary and the other is attached to the rotating assembly (e.g., a hub or shaft). As one of the bearing races rotates it causes the balls to rotate as well. Because the balls are rolling they have a much lower coefficient of friction than if two flat surfaces were sliding against each other.

Ball bearings tend to have lower load capacity for their size than other kinds of rolling-element bearings due to the smaller contact area between the balls and races. However, they can tolerate some misalignment of the inner and outer races.