Okuzeka
Physics vocabulary · Light and Optics

Electromagnetic spectrum

Meaning in physics, with examples

nounCore term

In physics, electromagnetic spectrum means: The full range of electromagnetic waves, ordered by wavelength or frequency: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma rays.

In Turkish: elektromanyetik spektrum, elektromanyetik tayf

How it is used

All parts of the spectrum travel at the same speed in a vacuum, about 3.00 × 10⁸ m/s. Going from radio waves to gamma rays, wavelength decreases while frequency and photon energy increase. Visible light is only a narrow band of the whole spectrum.

Example sentences

  1. X-rays and radio waves are both part of the electromagnetic spectrum.

  2. In the electromagnetic spectrum, ultraviolet lies just beyond violet light.

Common collocations

  • visible spectrum
  • electromagnetic radiation
  • electromagnetic waves
  • regions of the spectrum
  • wavelengthThe distance between two neighbouring points on a wave that are at the same stage of their cycle, such as two crests. It is shown by the Greek letter lambda (λ).
  • frequencyThe number of complete waves or oscillations that pass a point, or happen, each second. It is measured in hertz (Hz), where 1 Hz means one cycle per second.
  • photonA single packet, or quantum, of electromagnetic energy. Its energy depends only on the frequency of the radiation: E = hf, where h is Planck's constant.
  • waveA disturbance that travels through a medium or through space and carries energy from one place to another without carrying matter with it.
  • Doppler effectThe change in the observed frequency of a wave when the source and the observer move towards or away from each other. A siren sounds higher as it approaches and lower as it moves away.

More terms: Light and Optics

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