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) \(\frac{2 \ell}{3}\)
Ans(A)
