Suppose I a holding a box in my hands, and inside the box a spring with some mass attached hangs from the cieling of the box. Initial the system is at equilibrium, then I let go of the box and it falls. If I was inside the box observing what happens, what would I see.
Would the amplitude of oscillation change?
Would the period change? I think so, because the effective force constant of the spring is changed because we are now in a non-inertial reference frame.
The maximum speed reached by the mass, and the height above the bottom of the box at which the maximum speed is reached?
The maximum height reached by the mass?