An Electromagnetic Wave of frequency v = 3.0 MHz passes from vacuum into a dielectric medium with permittivity ε = 4.0. Them
Answer & explanation
Correct answer: option 3
In vacuum, $ε_0 = 1$
In medium,$ε = 4$
So, refractive index $ \mu = \sqrt{ε/ε_0} = \sqrt{4/1} = 2 $
wavelength $λ' = \frac{λ}{\mu}=\frac{λ}{2}$
and wave velocity $ v = \frac{c}{\mu}=\frac{c}{2}$
Hence, it is clear that wavelength and velocity will become half but frequency remains uncharged when the wave is passing through any medium.