Frequency of Light Waves in Full Spectrum

What is generally thought of as visible light is only a small part of the full electromagnetic spectrum. Radio waves, microwaves, infrared radiation, ultraviolet light, x-rays and gamma rays are all examples of the same phenomenon at different frequencies.

Frequency, Wavelength, and Energy

Frequency, the number of waves emitted per second, and wavelength, the size of each wave, are directly related. Multiplied together, they equal the speed of light. This means that they are inversely proportional; light with a very high wavelength has a very low frequency. The higher the frequency, the higher the energy of the light.

Visible Spectrum

Electromagnetic radiation, with wavelengths between 380 nanometers (nm) and 760 nm, are visible to the human eye. The frequencies of visible light range from 400 to 790 terahertz. Other animals, such as many snakes and birds, can see a wider spectrum. The high frequency, low wavelength end of the spectrum, known as violet light, has more energy than the low frequency, high wavelength end, which is perceived as red.

The Rest of the Spectrum

Wavelengths of light vary from 1 picometer (1/1,000,000,000,000 of a meter) in gamma rays to 100,000 kilometers in the weakest radio waves ever observed or created. Frequencies as low as 3 hertz and as high as 2,900,000,000,000,000,000,000,000,000 hertz have been observed.

References

• National Radio Astronomy Observatory: Pulsar Properties
• The Physics Hypertextbook: Electromagnetic Spectrum