A mass is attached to a spring supported from the ceiling of an elevator. We pull down on the mass and let it to vibrate. If the elevator starts to accelerate(fixed accelerate) upward, 1) How the maximum velocity changes? 2) How the amplitude changes? 3) How the total energy changes? I think the amplitude and maximum velocity does not change. Because the acceleration doesn't change the net force but only slide down the equilibrium point. Am i right?