Question

A small coin is put on the record rotating at 33⅓ rev/minute. The coin does not slip on the record. Where does it gets the required centripetal force from ?

Answer 1

Answer ⇒ Due to Frictional Force, the body gets the Centripetal force and it remains on  the Record.

Reason/Explanation  ⇒ When the Coin is placed on the Record, and it is rotating then Friction will try to balance the coin which will have tendency to move from record due to centrifugal force.

  f ≥ mv²/r

μmg ≥ mv²/r

v ≤ √(μrg)

If the Record will have the velocity equal to or less than the root of the μrg then the coin will not fall but if it becomes greater than that, then the body will fall out of the record because Friction cannot balance it.

Hope it helps.