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A body starts rotating from rest and com...

A body starts rotating from rest and completes 10 revolutions in 4 s .Find its angular acceleration

A

`2.5 pi rad//s^(2)`

B

`5 pi rad//s^(2)`

C

`7.5 pi rad //s^(2)`

D

`10 pi rad //s^(2)`

Text Solution

Verified by Experts

The correct Answer is:
A
`theta=omega_(1)t+(1)/(2)alphat^(2)`
`therefore 20 pi= 0+(1)/(2)xxalphaxx16`
`therefore alpha=(20pi)/(8)=2.5 rad//sec^(2)`.
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