Question

Four children were asked to arrange forces of friction in decreasing order, the correct arrangement is:
a)rolling,ststic,sliding
b)static,sliding,rolling
c)sliding,static,rolling
d)rolling sliding static

Answer 1

Sliding friction is the force of friction, below two objects, when one of them is sliding over the surface of the other. The force of sliding friction between them is a little smaller than static friction between them.

Between the same two surfaces, once motion is started the friction becomes slightly less than maximum static force rolling friction - force of friction that comes into play when one body rolls over the surface of another body.

It is more convenient to roll then to slide an object once the surface of other

Hence, static friction > sliding friction > Rolling friction.