A body rotating at 20 rad/sec is acted upon by a constant torque … - Vidyadip

MCQ

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 ...... $\sec.$

✓
$20$
B
$40$
C
$5$
D
$10$

✓

Answer

Correct option: A.

$20$

a
$\omega=\omega_{0}-\alpha t$

$-20=20-2 t$

$\therefore t=20 s$

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