17.1.1—The terms displacement, amplitude, period, frequency, angular frequency and

Displacement x measures position from equilibrium; amplitude A is maximum displacement; period T is cycle time; frequency f=1/T; angular frequency ω=2πf.

Keep phase and sign in displacement, while amplitude is a positive maximum. Use radians for angular frequency relationships.

A 5 Hz oscillator has T=0.20 s and ω=10π rad s⁻¹; its displacement alternates between ±A.

Amplitude is not peak-to-peak displacement, and angular frequency is not ordinary frequency in hertz.