Q 12-08-125JEE MainJEE Main 2022 (25 Jun, Shift 2)Easy
Electromagnetic waves travel in a medium at a speed of $2.0\times10^8\ \text{m s}^{-1}$. The relative permeability of the medium is $1.0$. The relative permittivity of the medium will be
Answer: (A) 2.25
$v = \dfrac{c}{\sqrt{\mu_r\varepsilon_r}}\Rightarrow\varepsilon_r = \left(\dfrac cv\right)^2 = \left(\dfrac{3}{2}\right)^2 = 2.25$.
Solution by Sreeraj P, M.Sc Physics