The frequency of an electromagnetic wave in free space is 2 MHz. When it passes through a region of relative permittivity εᵣ = 4.0, then its wavelength and frequency .

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(4) becomes half, remains constant. Given: 
u = 2 MHz in free space, then a medium with εᵣ = 4.0 (and μᵣ = 1). Idea: frequency is set by the source and does not change on entering a medium. What changes is the speed, and the wavelength follows from λ = v/
u. Refractive index: n = √μᵣεᵣ = √4.0 = 2. Speed in the medium: v = c/n = c/2, so λ = v/u is half its free-space value. So the wavelength becomes half and the frequency remains constant.

The frequency of an electromagnetic wave in free space is 2 MHz. When it passes through a region of relative permittivity εᵣ = 4.0, then its wavelength and frequency .

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The frequency of an electromagnetic wave in free space is 2 MHz. When it passes through a region of relative permittivity εᵣ = 4.0, then its wavelength ______ and frequency ______.

Step-by-step solution

Why the other options are wrong

The frequency of an electromagnetic wave in free space is 2 MHz. When it passes through a region of relative permittivity εᵣ = 4.0, then its wavelength and frequency .