WBJEE · Physics · Rotational Motion
A uniform rod of length \(L\) pivoted at one end \(P\) is freely rotated in a horizontal plane with an angular velocity \(\omega\) about a vertical axis passing through \(\mathrm{P}\). If the temperature of the system is increased by \(\Delta \mathrm{T}\), angular velocity becomes \(\frac{\omega}{2}\). If coefficient of linear expansion of the rod is \(\alpha(\alpha< < 1)\), then \(\Delta \mathrm{T}\) will be
- A \(\frac{1}{\alpha}\)
- B \(\frac{1}{2 \alpha}\)
- C \(\frac{1}{4 \alpha}\)
- D \(\alpha\)
Answer & Solution
Correct Answer
(B) \(\frac{1}{2 \alpha}\)
Step-by-step Solution
Detailed explanation
\(\mathrm{I} \omega=\mathrm{I}_{1} \frac{\omega}{2}\) \(\quad \mathrm{I}_{1}=2 \mathrm{I}\) \(\quad \frac{\mathrm{ml}_{1}^{2}}{3}=2 \frac{\mathrm{ml}_{0}^{2}}{3}\)…
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