A bob of mass m attached to an inextensible string of length I is suspended from a vertical support. The bob rotates in a horizontal circle with an angular speed `omega` red/s about the vertical. About the point of suspension:
A
angular momentum is conserved.
B
angular momentum changes in magnitude but not is direction.
C
angular momentum changes in direction but not in magnitude.
D
angular momentum changes both in direction and magnitude.
Text Solution
Verified by Experts
The correct Answer is:
C
(c ) Torque working on the bob of mass m is, `tau = mgxxisin theta.` (Direction parallel to plane of rotation of particle) As `tau` is perpendicular to `vecL` direction of L changes but magnitude remains same.
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