A metre scale is moving with uniform velocity.
Question:

A metre scale is moving with uniform velocity. This implied

(a) the force acting on the scale is zero, but a torque about the centre of mass can act on the scale

(b) the force acting on the scale is zero and the torque acting about the centre of mass of the scale is also zero

(c) the total force acting on it need not be zero but the torque on it is zero

(d) neither the force nor the torque needs to be zero

Solution:

The correct answer is (b) the force acting on the scale is zero and the torque acting about the centre of mass of the scale is also zero