Question

Most machines use ball bearings to reduce the energy lost in friction since rolling friction is smaller than sliding friction.

• A. Less
• B. False

Answer 1

The correct option is A Less

Ball bearings are used in most of the machines to reduce energy loss. This is because ball bearings involve rolling friction instead of sliding friction. Rolling friction is always smaller than sliding friction as the area of surface in contact in the case of rolling friction is less than that in the case of sliding friction. Hence, the given statement is true.
Common examples are the use of ball bearings between the hubs and the axles of ceiling fans and bikes.