Electromagnetic waves travel in a medium with speed of $1.5 \times 10^8 \mathrm{~m} \mathrm{~s}^{-1}$. The relative permeability of the medium is 2.0. The relative permittivity will be:
Solution
<p>$$\begin{aligned}
& v=\frac{1}{\sqrt{\mu_0 \mu_r \varepsilon_0 \cdot \varepsilon_r}} \\
& \Rightarrow 1.5 \times 10^8=\frac{3 \times 10^8}{\sqrt{2 \cdot \varepsilon_r}} \Rightarrow \varepsilon_r=2
\end{aligned}$$</p>
About this question
Subject: Physics · Chapter: Electromagnetic Waves · Topic: Properties of EM Waves
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