according to energy conservation
mg2lsin30∘=213ml2ω2
Solving
ω2=15
ω=15
JEE Main 2020 — Physics Mechanics
One end of a straight uniform 1m long bar is pivoted on horizontal table. It is released from rest when it makes an angle 30o from the horizontal (see figure). Its angular speed when it hits the table is given as nrads−1 , where n is an integer. The value of n is ____________

Held on 9 Jan 2020 · Verified 6 Jul 2026.
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