The number of complete wave cycles that pass a fixed point per second. Measured in Hertz (Hz). Higher frequency means more cycles per second and a higher-pitched sound.
The distance between two adjacent points in phase — for example, crest to crest or trough to trough. Symbol: λ (lambda). Measured in metres.
How fast the wave travels through a medium. It depends on the medium — not the source. All electromagnetic waves travel at c = 3×10⁸ m/s in a vacuum.
The time taken for one complete oscillation. Period and frequency are reciprocals: doubling the frequency halves the period.
The maximum displacement from the equilibrium position. Amplitude is related to the energy carried by a wave — larger amplitude = more energy.
When two waves overlap, the resultant displacement is the sum of individual displacements. Constructive interference increases amplitude; destructive interference reduces it.