A bob of mass \(m\) attached to an inextensible string of length \(l\) is suspended from a vertical support. The bob rotates in a horizontal circle with an angular speed \(\omega\ rad/s\) about the vertical. About the point of suspension:

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Answer & Solution

Correct Answer

(B) angular momentum changes in direction but not in magnitude

Step-by-step Solution

Detailed explanation

Torque working on the bob of mass \(m\) is,

\(\tau = mg \times \ell \sin \theta .\,\). (Direction parallel to plane of rotation of particle)

As \(\tau \) is perpendicular to \(\overrightarrow L \), direction of \(L\) changes but magnitude remains same.

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