Similarities

Like all waves, electromagnetic waves are characterised by their wavelength (the distance between two disturbances or oscillations), their frequency (the time that it takes for one complete oscillation to pass a given point), and their speed. All electromagnetic waves are found to have the same speed, the speed of light. Since all electromagnetic waves travel at the same speed, as the wavelength increases, or gets longer, the frequency decreases, or it takes more time for the longer wave to pass.

It should not be surprising that all electromagnetic waves travel at the same speed as light, because light itself is just a form of electromagnetic radiation that humans are capable of detecting. Infrared radiation, ultraviolet radition, radiowaves, microwaves, all are just electromagnetic waves of a different frequency and wavelength.

The following image shows how different types of radiation are just different wavelength electromagnetic waves.

an image of the elctromagnetic spectrum with wavelength, frequency, and energy specified.

This image is courtesy of Imagine the Universe.

The frequency ($\nu$, sometimes denoted by f) and the wavelength ($\lambda$) of a given wave are related by

\begin{displaymath} \lambda \nu = c \end{displaymath}

where c is the speed of light, 3.00E08 m/s. The standard unit of frequency is cycles per second, or Hz.
Quick Quiz: What is the frequency of 0.5 micron light?
6.0E14
6.0E8
1.5E14
1.5E08

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