A box experiencing a gravitational force of 600 N. is being pulled to the right with a force of 250 NA 25 N. frictional force acts on the box as it moves to the right what is the net force in the Y direction

Why does the equilibrium position of the spring change when a mass is added to the spring? will the mass oscillate around the new equilibrium position of the spring or the previous position without a mass attached to the spring? if the equilibrium position of the spring changes by 20 cm (assuming no initial mass) when a mass is added to the spring with constant 4.9 kg/s^2, what is the mass of the object attached to the spring?