Question

when the fnet=0 at what situation is object moving at a constant velocity or not moving at all ?

Answer 1

if the position of the object remains the same with time, it's not moving at all. but if rate of change of position is constant,then velocity is constant and fnet=0

Answer 2

For a body to be in equilibrium both the net force as well as net moment acting on the body should be zero. We just cannot say whether a body is at rest or in uniform motion given that net force is zero.

Answer 3

So the net force is zero but the object could still have energy if the velocity is not zero

Answer 4

If velocity is non-zero the object obviously has Kinetic Energy. Even if it is at rest it possess Potential Energy due to position, heat energy due to temperature or light energy due to luminosity.