Question

where on bicycle can friction be very useful​

Answer 1

There is sliding friction between the brake pads and bike rims each time you use your bike's brakes. This friction slows the rolling wheels so you can stop. Rolling friction is friction that acts on objects when they are rolling over a surface.

Answer 2

Answer:

The brake pads and the wheel rims have friction when we brake. There is friction between the handlebar and the hands that allows for a successful gripping. The bike tire and the road have some friction so that we can actually roll the bike wheels safely without sliding.