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A uniform square plate of mass 2.0 kg an...

A uniform square plate of mass 2.0 kg and edge 10 cm rotates about one of its diagonals under the action of a constant torque of 0.10 Nm. Calculate the angular momentum and the kinetic energy of the plate at the end of the fifth second after the start.

Text Solution

Verified by Experts

The correct Answer is:
B
`I=0.10N, a=10cm=0.1m,m=2kg`
Therefore `(ma^2)/12)xxa=0.1N-m`
`rarr alpha=60rad/s`

Therefore `omega=omega_0+at`
`rarr omega=60xx5=300rad/s
Therefore angular mometum
`=Iomega=(0.10/60)xx300`
`=0.50kg-m^2/s`
`and kinetic energy `=1/2x(0.10/60)xx300^2`
=27jule
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