Question
A body rotating at $20\ rad/sec$ is acted upon by a constant torque providing it a deceleration of $2\ rad/sec^2$. At what time will the body have kinetic energy same as the initial value if the torque continues to act ...... $\sec.$
✓
Answer
$\omega=\omega_{0}-\alpha t$
$-20=20-2 t$
$\therefore t=20 s$
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