JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
A thin solid disk of 1 kg is rotating along its diameter axis at the speed of 1800 rpm. By applying an external torque of \(25 \pi \mathrm{Nm}\) for 40 s, the speed increases to 2100 rpm. The diameter of the disk is ________ m.
- A 60
- B 50
- C 40
- D 30
Answer & Solution
Correct Answer
(C) 40
Step-by-step Solution
Detailed explanation
Given, \(\mathrm{m}=1 \mathrm{~kg}\)…
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