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Question
If the relative permeability and relative permittivity of the medium is 1.0 and 2.25, respectively. Find the speed of the electromagnetic wave in this medium.
Solution
Relative permeability of the medium, μr = 1
Relative permitivity of the medium, εr = 2.25
`(epsilon_"r" = epsilon/epsilon_0 and mu_"r" = mu/mu_0)`
Speed of electromagnetic wave, v = `1/sqrt (mu epsilon)`
`= 1/sqrt(mu_"r"mu_0epsilon_"r"epsilon_0) = "C"/sqrt(mu_"r" epsilon_"r")` ....`["where", "C" = 1/sqrt(mu_0epsilon_0)]`
`= (3 xx 10^8)/(sqrt(1 xx 2.25))`
`= (3 xx 10^8)/1.5`
v = `2 xx 10^8`ms-1
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