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A metal coin of mass 5 g and radius 1 cm...

A metal coin of mass 5 g and radius 1 cm is fixed to a thin stick AB of negligible massas shown in the figure. The system in initially at rest. The constant torque (in Nm) that will make the system rotate about AB at 25 rotations per second in 5s, is close to:

Text Solution

Verified by Experts

Angular acceleration
`alpha=(omega-omega_(0))/t`
`=(25xx2pi-0)/5`
`=10pi"rad"//s^(2)`
`tau=I alpha`
`impliestau=(5/4mR^(2))alpha`
`~~(5/4)(5xx10^(-3))(10^(-4))10pi`
`=2.0xx10^(-5)Nm`
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