Question

There is a ruler rotating, will it have a net force?

Answer 1

if the ruler is rotating at constant angular velocity (and there are no opposing forces acting) then there is no net force on the ruler. If it is accelerating (non-zero angular acceleration), then there is a net force (torque) acting on the ruler.

Answer 2

it depends upon the axis of rotation.... if it is at its centre of mass then the net force is zero and at any other place it is not = 0

Answer 3

the very fact that the ruler is rotating is beacuse of an external torques now the question comes
is it rotaing with a constant angular velocity omega and hence constant velocity v
if so then there is no net forces acting on it
we have to remeber here taht
tow= r X F

Answer 4

if the ruler is rotating with constant angular velocity , it will have its angular momentum conserved hence no external torque.
also it cant be assumed that there is no net force because may be non zero net forces like m*g may be acting and may be passing through axis of rotation hence giving no net torque
we should also consider frame of reference if it is accelerating it will have non zero net force

Answer 5

yes there is a net force which is the force that keeps it in motion.