
Normal force acting on the coin is, N=mg.
Required friction force to provide centripetal force for the coin is, f=mω2r and maximum value of static friction force available is, f=μN=μmg.
For limiting condition, we can write
⇒μmg=mrω2
⇒ω=rμg
A coin is placed on a disc. The coefficient of friction between the coin and the disc is μ. If the distance of the coin from the center of the disc is r, the maximum angular velocity which can be given to the disc, so that the coin does not slip away, is :
Held on 31 Jan 2024 · Verified 6 Jul 2026.
rμg
μgr
rμg
rgμ
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