max displacement mm equilibrium A block is attached to one end of a spring with the other end of the spring fixed to a wall. The block is vibrating horizontally on a frictionless surface and has a maximum displacement from the equilibrium point, A. If the 1.5-kg block is moving 20 cm/s half-way between the equilibrium position and A, what is the total energy of the system? Hint: at the maximum displacement, all the energy is elastic potential energy