WBJEE · Physics · Rotational Motion
A simple pendulum of length \(\ell\) is displaced so that its taught string is horizontal and then released. A uniform bar pivoted at one end is simultaneously released from its horizontal position. If their motions are synchronous, what is the length of the bar?
- A \(\frac{3 \ell}{2}\)
- B \(\ell\)
- C \(2 \ell\)
- D \(\frac{2 \ell}{3}\)
Answer & Solution
Correct Answer
(A) \(\frac{3 \ell}{2}\)
Step-by-step Solution
Detailed explanation
Hint: \(v=\sqrt{2 g h}\) \(=\sqrt{2 g \mid \sin \theta}\) \(\omega_{1}=\frac{v}{l}=\sqrt{\frac{2 g \sin \theta}{1}}\) \(m g h=\frac{1}{2} l \omega^{2}\)…
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