Q 12-08-056JEE MainJEE Main 2024 (6 Apr, Shift 1)Easy
Electromagnetic waves travel in a medium with a speed of $1.5\times10^8\ \text{m s}^{-1}$. The relative permeability of the medium is $2.0$. The relative permittivity will be
Answer: (A) $2$
$v = \dfrac{c}{\sqrt{\mu_r\varepsilon_r}} \Rightarrow \mu_r\varepsilon_r = \left(\dfrac{3\times10^8}{1.5\times10^8}\right)^2 = 4 \Rightarrow \varepsilon_r = \dfrac42 = 2$.
Solution by Sreeraj P, M.Sc Physics