Electromagnetic spectrum

Electromagnetic Spectrum is the range of all possible frequencies of electromagnetic radiation. The electromagnetic spectrum extends from below the low frequencies used for modern radio communication to gamma radiation at the short-wavelength (high-frequency) end, thereby covering wavelengths from thousands of kilometers down to a fraction of the size of an atom.

Overview

The electromagnetic spectrum is a continuum of all electromagnetic waves arranged according to frequency and wavelength. The sun, earth, and other bodies radiate electromagnetic energy of varying wavelengths. Electromagnetic energy passes through space at the speed of light in a manner similar to the way that a wave's energy travels through water.

Types of Electromagnetic Waves

The electromagnetic spectrum is generally divided into seven regions, in order of decreasing wavelength and increasing energy and frequency. The common designations are: radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV), X-rays and gamma rays.

Radio Waves

Radio waves have the longest wavelength in the electromagnetic spectrum. They are used for transmitting television and radio broadcasts.

Microwaves

Microwaves are used for high-speed microwave communication and heating of food in microwave ovens.

Infrared Waves

Infrared waves are used for physical therapy, heat lamps, and also in remote controls for televisions.

Visible Light

Visible light is the portion of the electromagnetic spectrum that is visible to the human eye.

Ultraviolet Waves

Ultraviolet waves are used in tanning booths and can also cause skin cancer.

X-Rays

X-rays are used for medical imaging.

Gamma Rays

Gamma rays are used in radiation therapy to treat cancer and in nuclear power plants.

See Also

• Light
• Radiation
• Wavelength
• Frequency

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  Properties of the electromagnetic spectrum
• Diagram of the electromagnetic spectrum
  Diagram of the electromagnetic spectrum
• NASA illustration of the electromagnetic spectrum
  NASA illustration of the electromagnetic spectrum
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  Atmospheric electromagnetic opacity
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  Atmospheric absorption of electromagnetic waves (2013)
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  Ozone altitude and UV graph