give example where we use to decrease friction
Kindly refer the similar link below.
https://www.meritnation.com/ask-answer/question/does-use-of-ball-bearings-increase-friction-or-decrease-fric/friction/8013621
https://www.meritnation.com/ask-answer/question/does-use-of-ball-bearings-increase-friction-or-decrease-fric/friction/8013621