Physics · 2019
JEE Main · 9 April 2019, Shift 1 · Q7
A stationary horizontal disc is free to rotate about its axis. When a torque is applied on it, its kinetic energy as a function of θ, where θ is the…
A stationary horizontal disc is free to rotate about its axis. When a torque is applied on it, its kinetic energy as a function of $\displaystyle \theta$, where $\displaystyle \theta$ is the angle by which it has rotated, is given as $\displaystyle \mathrm{k} \theta^2$. If its moment of inertia is I then the angular acceleration of the disc is :
Official answer
(2)
$\displaystyle \frac{2 \mathrm{k}}{\mathrm{I}} \theta$
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JEE Main 2019 Physics question, with the answer from NTA’s final answer key. Where our answers come from.