Moment of a force about O is lα=mg2lsinθ
⇒α=32ml2mglsinθ
⇒α=2l3gsinθ
JEE Main 2017 — Physics Mechanics
A slender uniform rod of mass M and length l is pivoted at one end so that it can rotate in a vertical plane (see figure). There is negligible friction at the pivot. The free end is held vertically above the pivot and then released. The angular acceleration of the rod when it makes an angle θ with the vertical is:

Held on 2 Apr 2017 · Verified 6 Jul 2026.
3l2gcosθ
2l3gsinθ
3l2gsinθ
2l3gcosθ
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