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A rotating wheel changes angular speed f...

A rotating wheel changes angular speed from 1800 rpm to 3000 rpm in 20 s. What is the angular acceleration assuming to be uniform ?

A

`60pi` rad `s^(-2)`

B

`90pi` rad `s^(-2)`

C

`2pi` rad `s^(-2)`

D

`40pi` rad `s^(-2)`

Text Solution

Verified by Experts

The correct Answer is:
C
`v_(0)=(1800)/(60)=30Hz therefore omega_(0)=2piv_(0)=60pi" rad/s"`
`v=(3000)/(60)=50Hz therefore omega=2piv=100pi" "rad/s`
Angular acceleration `a=(omega-omega_(0))/(t)=(100pi-60pi)/(20)=2omega" rad/s"`
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