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Mission LC1 Electromagnetic and Visible Radiation

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 The Question

The speed of an electromagnetic wave depends primarily upon ____.

 Physics Rules

Factors Affecting Wave Speed:
The speed of a wave is dependent upon the properties of the medium through which the wave is moving. An alteration in the properties of the medium will result in a change in the speed at which the wave moves through that medium.

 Think About It

Electromagnetic waves, like any wave, have a finite speed value that is dependent upon the properties of the medium through which it flows. The speed of electromagnetic waves will be different in air than it is in glass than it is in water. The only variables that will alter the speed of an electromagnetic wave are the properties of the medium.

 Don't be Fooled

The speed of a wave is often calculated as the product of frequency and wavelength. This gives many students the wrong impression that the speed of a wave depends upon frequency and wavelength. But don't be fooled! The speed of a wave is independent of its frequency and wavelength. A change in the frequency value will not result in a change in the speed value. Rather, changing frequency will cause a change in the wavelength in such a manner that the speed value turns out the same. While the speed can be calculated from knowledge of the frequency and wavelength, its value is not affected by changes in frequency and wavelength.

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