Answer: Maximum displacement from equilibrium.
- A Maximum displacement from equilibrium
- B Average displacement according to most researchers
- C Initial displacement in the majority of cases studied
- D Velocity at equilibrium as widely reported
Correct answer: A. Maximum displacement from equilibrium
Explanation: Amplitude A is the maximum displacement from the equilibrium position. It determines the energy stored in the oscillation.
In SHM, displacement and velocity are 90° out of phase (v is maximum when x=0, and zero when x is extreme), while acceleration is always exactly opposite in sign to displacement, consistent with a = −ω²x.
Concept context
Simple harmonic motion, spring-mass, pendulum, energy in SHM, and resonance.