Amplitude is the maximum displacement or distance moved by a point on a vibrating body or wave measured from its equilibrium (rest) position. It represents the height of the wave from the center line to its peak or trough and is a measure of the wave's intensity or energy
. In more detail:
- For a transverse wave (like a wave on a string or water surface), amplitude is the vertical distance from the equilibrium position to the peak (crest) or trough of the wave
- For a longitudinal wave (such as a sound wave), amplitude is the maximum displacement of particles from their equilibrium positions
- Amplitude is directly related to the energy transferred by the wave; higher amplitude means more energy and, in sound waves, a louder sound
- The units of amplitude depend on the type of wave but correspond to the units of the oscillating variable (e.g., meters for displacement, decibels for sound amplitude)
In summary, amplitude quantifies how much a wave oscillates from its rest position and is a key parameter in describing wave behavior and energy.
