Question

If friction does'nt depend on surface area of contact between the two surfaces then why sliding friction is higher than rolling friction??please help really tangled with this one...

Answer 1

@irishboy123

Answer 2

@arindameducationusc

Answer 3

@michele_laino

Answer 4

Its an experimental result, sliding friction increases until the force that tries to produce the movement exceed the maximum of sliding friction and then the friction force starts to do less force than when the object wasnt moving.

Answer 5

It is experimentally observed but i think there is a microscopic explanation about why it happens but i disown it.

Answer 6

I understand what you are willing to say but i think you did'nt get my point...i was saying that if friction do not depend on surface area of contact which is obviously macroscopic....so why it is harder to drag a cube of same mass than a wheel of identical mass and weight...it means a cube have greater friction bcoz it have greater surface area of contact than a wheel...as far as i know friction only depends on foce normal to it which is weight of the body and as both the cube and the wheel have same weight so there should be the same effort dragging any of them...

Answer 7

@EmmaTassone

Answer 8

If the cube and the wheel are made of the same material, I think it shouldnt be harder to drag the cube

Answer 9

Then why we use wheel for our cars not cubes????? @emmatassone

Answer 10

because the wheel rolls and the cube doesn't. The fact is that if we drag a wheel, without making it rolling, it wont be harder to drag the wheel or the cube if they are made of the same material.

Answer 11

Hmmmm

Answer 12

It means the convenience in the case of the wheel is because of rolling...is'nt it???

Answer 13

yep

Answer 14

The fact that the wheels can roll doesnt mean they have more friction than cubes which cant roll because of they geometry.