Restoring Force: In this ideal system, the mass is subject to a restoring force F = −kx. This linear relationship ensures the acceleration is always directed towards the equilibrium (x = 0).

Phase Relationship: Velocity (v) leads displacement (x) by 90°. Acceleration (a) is 180° out of phase with displacement — maximum positive when displacement is maximum negative.

Conservation of Energy: Velocity is zero at the extremes (±A) where potential energy is maximum. Velocity peaks at the center (x = 0) where kinetic energy is maximum.