Physics · 2019
JEE Main · 10 April 2019, Shift 2 · Q7
A metal coin of mass 5 g and radius 1 cm is fixed to a thin stick AB of negligible mass as shown in the figure. The system is initially at rest. The…
A metal coin of mass $\displaystyle 5$ g and radius $\displaystyle 1$ cm is fixed to a thin stick AB of negligible mass as shown in the figure. The system is initially at rest. The constant torque, that will make the system rotate about AB at $\displaystyle 25$ rotations per second in $\displaystyle 5$ s, is close to :
Official answer
(4)
$\displaystyle 2.0 \times 10^{-5} \mathrm{Nm}$
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JEE Main 2019 Physics question, with the answer from NTA’s final answer key. Where our answers come from.