WBJEE · Physics · Rotational Motion
A small ball of mass \(m\) is suspended from the ceiling of a floor by a string of length \(L\). The ball moves along a horizontal circle with constant angular velocity \(\omega\), as shown in the figure. The torque about the centre ( O ) of the horizontal circle is
- A \(m g L \sin \theta\)
- B mg L
- C 0
- D \(m g L \cos \theta\)
Answer & Solution
Correct Answer
(C) 0
Step-by-step Solution
Detailed explanation
Hint : Angular momentum is conserved about O.
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