JEE Main 2019 — Rotational Motion Question with Solution
From: JEE Main 2019 (Online) 10th April Evening Slot
Question
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 constant torque, that will make the system rotate about AB at 25
rotations per second in 5s, is close to :
This question includes a diagram. The text above accompanies the figure.
Choose an option
Show full solutionCorrect option: C
Correct answer
C2.0 × 10–5 Nm
Step-by-step explanation
m = 5 × 10–3 kg, r = 10–2 m
= 25 × 2 rad/5
= 50 rad/sec
Nm
= 25 × 2 rad/5
= 50 rad/sec
Nm
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This is a previous-year question from JEE Main 2019, covering the Rotational Motion chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.