Physics GCSE
red-shift
What red-shift means in Physics GCSE, as defined for AQA.
Definitions of red-shift
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Reference: AQA
An observed increase in the wavelength of light from most distant galaxies, called red-shift because red is the longest wavelength of visible light.
The effect in which the lines in a galaxy's spectrum shift towards longer wavelengths, towards the red end of the visible spectrum.
Topics that use red-shift
- Red-shift (physics only) (AQA GCSE)
Related terms
- absorption line spectra
- accelerating expansion
- dark energy
- dark mass and dark energy
- expanding universe
- increase in wavelength
- measuring distance
- receding galaxies
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