Amplitude

Definition

Amplitude is the maximum displacement of a wave or oscillating object from its equilibrium position. It measures the extent of change in the wave's physical quantity such as height or pressure.

5 Must Know Facts For Your Next Test

1. In simple harmonic motion, amplitude is the distance from the equilibrium position to the maximum displacement.
2. Amplitude is directly related to the energy carried by a wave; higher amplitude means higher energy.
3. For electromagnetic waves, amplitude corresponds to the peak value of electric and magnetic field strengths.
4. Amplitude does not affect the frequency or wavelength of a wave but influences its intensity.
5. In a pendulum, amplitude can be measured as the maximum angular displacement from the vertical.

Review Questions

• What is amplitude in simple harmonic motion?
• How does amplitude relate to the energy of an electromagnetic wave?
• Does amplitude affect the frequency or wavelength of a wave?

Related terms

Frequency:

The number of complete oscillations or cycles per unit time. Measured in Hertz (Hz).

Wavelength:

The distance between successive crests, troughs, or identical points in a wave. Usually denoted by $\lambda$.

Period:

The time taken for one complete cycle of oscillation. It is inversely related to frequency.