Wavelength

Definition

Wavelength is the distance between successive crests or troughs of a wave, typically measured in meters. It is a fundamental property of waves, including electromagnetic waves such as light.

5 Must Know Facts For Your Next Test

1. Wavelength ($\lambda$) is inversely proportional to frequency ($f$) according to the equation $c = \lambda f$, where $c$ is the speed of light.
2. Wavelength determines the color of visible light, with shorter wavelengths corresponding to blue/violet and longer wavelengths corresponding to red.
3. In the electromagnetic spectrum, wavelength ranges from gamma rays (shortest) to radio waves (longest).
4. Energy ($E$) of a photon is related to its wavelength by the equation $E = \frac{hc}{\lambda}$, where $h$ is Planck's constant and $c$ is the speed of light.
5. Measurement units for wavelength can vary but are often expressed in meters (m), nanometers (nm), or angstroms (Å).

Review Questions

• How does wavelength relate to frequency?
• What happens to the energy of a photon as its wavelength decreases?
• How does wavelength determine the color of visible light?

Related terms

Frequency:

The number of wave cycles that pass a given point per unit time, typically measured in Hertz (Hz).

Electromagnetic Spectrum:

The range of all types of electromagnetic radiation, from gamma rays to radio waves.

Photon: A quantum of electromagnetic energy with both particle and wave properties; its energy depends on its wavelength.