The speed of an electromagnetic wave in a material medium is given by v = 1/√µɛ , µ being the permeability of the medium and ɛ its permittivity. How does its frequency change?

The frequency of an electromagnetic wave does not change in a material medium, as it depends solely on the source. However, the wave’s speed and wavelength decrease due to the medium’s permeability (µ) and permittivity (ɛ).

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