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Grade 11Mechanics

a coin is kept a distance of 10cms from the centre of a turnable table .If the coefficient of static friction is 0.8 find the frequency of rotation of the disc at which the coin will begin to slip

Soumith kumar

9 Years agoGrade 11

1 Answer

Pushkar Prateek

9 Years ago

Suppose the turn table rotates with angular (frequency or speed) $\omega$ rad/s. Here, friction will provide the required centripetal force.

The coin will begin to slip when required centripetal force just exceeds maximum possible friction.

So in limiting condition

Centripetal force required for circular motion of the coin just becomes equal to maximum possible friction.

0.8mg = m $\omega$ ² 0.1

$\omega$ = 4 $\sqrt{5}$ rad/s.

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