Two boys are trying to push a sofa, with each of them exerting a force of 120N. Note that the sofa is in the middle of the room and not in contact with any of the walls and yet, it will not budge. What is the friction exerted by the floor on the sofa?
If an outside force attempts to move an object that is on a surface but did not move, it means that friction is already resisting attempts to move it. An object that is not moving is in state of equilibrium.
