Amplitude is still the displacement from the equilibrium, wavelength is still the distance between two identical points on the wave, and period is still the time for one cycle to complete. The side to...Amplitude is still the displacement from the equilibrium, wavelength is still the distance between two identical points on the wave, and period is still the time for one cycle to complete. The side to side shaking that happens in an earthquake is the result of a longitudinal wave, as is the sound wave produced by the movement of a speaker cone or the vibration of a guitar string.
