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Here is an overview of the electromagnetic spectrum. There are different types of graphics shown: emitting devices, receiving devices or simple illustrative symbols.

Since electromagnetic waves propagate at a constant speed (speed of light), the frequency and the wavelength remain in a constant ratio.

**Click** and **drag** the ruler to shift it horizontally

- To have an overview of the whole electromagnetic spectrum.
- To make the link between wavelength and frequency.

An electromagnetic wave is characterized by its **frequency**, f (expressed in Hertz) or, its **wavelength**, λ (expressed in meters). It travels in a vacuum at the speed of light, c = 300,000…