Question

why rolling friction is less than the sliding friction​

Answer 1

friction reduces if the force acting on the object is less as friction is a force.

so when you slide the object the face of the object touches the ground and hence more force is applied to move it forward .

but when we roll the only part in contact to the ground is the ball bearings are the wheel so here the friction is less .

HENCE ROLLING FRICTION IS LESS THAN SLIDING FRICTION .

Answer 2

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Sliding friction - two objects are in contact with each other when one of them is just slide over another is called sliding friction.

Rolling friction - two objects are in contact with each other when one of them is slide over another.

It is always easier to roll than to slide an object over another object. So rolling friction is much less than the sliding friction.

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