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Science

The electromagnetic spectrum

Electromagnetic radiationelectromagnetic radiation: Energy travelling as waves in the form of changing electrical and magnetic fields. travels as waves and transfers energy from one place to another. All electromagnetic waves can travel through a vacuum, and they all travel at the same speed in a vacuum.

The electromagnetic spectrum is a continuous range of wavelengths. The types of radiation that occur in different parts of the spectrum have different uses and dangers, which depend on their wavelength and frequency.

What is a spectrum?

The visible spectrum

a rainbow appears to come out of the prism

Refraction from a prism

White light can be split up using a prism to form a spectrum. A prism is a block of glass with a triangular cross-section. The light waves are refracted as they enter and leave the prism. The shorter the wavelength of the light, the more it is refracted. As a result, red light is refracted the least and violet light is refracted the most, causing the coloured light to spread out to form a spectrum.

The electromagnetic spectrum

Visible light is just one type of electromagnetic radiation. There are various types of electromagnetic radiation, some with longer wavelengths than visible light and some with shorter wavelengths than visible light.

Back to Radiation and the Universe index

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