Question

Why is it advantageous to use ball bearings between machine surfaces?

• A. Sliding friction is less than rolling friction.
• B. Rolling friction is less than sliding friction.
• C. Sliding friction is equal to rolling friction.
• D. Static friction is more than sliding friction.

Answer 1

The correct option is B Rolling friction is less than sliding friction.

Rolling friction is the resistance to motion experienced by a body when it rolls on another surface. It is much lesser than sliding friction for the same pair of bodies. Thus, when ball bearings are used in between two machine surfaces, sliding friction between them will be replaced by rolling friction.