7. A 1.00 kg mass is connected to a spring with a spring constant of 9.00 N/m. If the initial velocity is 4.00 cm/s and the initial displacement is 0.00 cm, then A) what is the maximum spring potential energy of the simple harmonic motion

At the equilibrium position of the spring, the mass has kinetic energy

1/2 (1.00 kg) (0.0400 m/s)² = 0.000800 J = 0.800 mJ = 800 µJ

and when the spring is maximally compressed, this kinetic energy is converted into potential energy.

truck y has a greater velocity than truck x.