A disc of moment of inertia `9.8//pi^(2)kg m^(2)` is rotating at 600 rpm. If the frequency of rotation changes from 600 rpm to 300 rpm, then what is the work done ?A. 1567 JB. 1452 JC. 1467 JD. 1632 J

A disc of moment of inertia `9.8//pi^(2)kg m^(2)` is rotating at 600 r

1.	A disc of moment of inertia `9.8//pi^(2)kg m^(2)` is rotating at 600 rpm. If the frequency of rotation changes from 600 rpm to 300 rpm, then what is the work done ?A. 1567 JB. 1452 JC. 1467 JD. 1632 J
Answer» Correct Answer - C `omega = KE_(2)-KE_(1)=(1)/(2)I (omega_(2)^(2)-omega_(1)^(2))` `= (1)/(2)xx(9.8)/(pi^(2))xx4 pi^(2)(n_(2)^(2)-n_(1)^(2))` `= 4.9xx4(25-100)` `=4.9xx4xx75` `= 4.9xx300` `= 1470.0` `= 1467 J`

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A disc of moment of inertia `9.8//pi^(2)kg m^(2)` is rotating at 600 rpm. If the frequency of rotation changes from 600 rpm to 300 rpm, then what is the work done ?A. 1567 JB. 1452 JC. 1467 JD. 1632 J

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