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A coin is placed on the horizontal surfa...

A coin is placed on the horizontal surface of a rotation disc. The distance of the coin from the axis is 1 m and coefficient of friction is 0.5. If the disc starts from rest and is given an angular acceleration `(1)/(sqrt(2))` rad /`sec^(2)`, the number of revolutions through which the disc turns before the coin slips is

A

`(4)/(pi)`

B

`(7)/(4pi)`

C

`(5)/(4pi)`

D

`(3)/(4pi)`

Text Solution

Verified by Experts

The correct Answer is:
B
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