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Question
A metre scale is moving with uniform velocity. This implies ______.
Options
the force acting on the scale is zero, but a torque about the centre of mass can act on the scale.
the force acting on the scale is zero and the torque acting about centre of mass of the scale is also zero.
the total force acting on it need not be zero but the torque on it is zero.
neither the force nor the torque need to be zero.
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Solution
A metre scale is moving with uniform velocity. This implies the force acting on the scale is zero and the torque acting about centre of mass of the scale is also zero.
Explanation:
Since the body is moving with a uniform velocity, hence its acceleration is zero. This implies that the net force acting on it must be zero, which further makes the torque acting about the centre of mass of the scale also zero.
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