Jee Main
Electromagnetic Waves
JEE Main 2023 (Online) 31st January Morning Shift
INTEGER+4 / -12023
In a medium the speed of light wave decreases to \(0.2\) times to its speed in free space The ratio of relative permittivity to the refractive index of the medium is \(x: 1\). The value of \(x\) is _________.
(Given speed of light in free space \(=3 \times 10^{8} \mathrm{~m} \mathrm{~s}^{-1}\) and for the given medium \(\mu_{\mathrm{r}}=1\))