Electromagnetic waves travel in a medium with speed of 1.5 × 10 8 ms -1 . The relative permeability of the medium is 2.0 . The relative permittivity will be :

Physics · Electromagnetic Waves

JEE Main 2024 — 6 April, Shift 1 — Question 35

Electromagnetic waves travel in a medium with speed of $1.5 \times 10^{8} \mathrm{~ms}^{-1}$ . The relative permeability of the medium is 2.0 . The relative permittivity will be :

Option A:
5
Option B:
1
Option C:
4
Option D:
2
Correct

Answer: D

Step-by-step solution

$\frac{\varepsilon_{\mathrm{m}} \times \mu_{\mathrm{m}}}{\varepsilon_{0} \times \mu_{0}}=\frac{\frac{1}{\mathrm{v}^{2}}}{\frac{1}{\mathrm{c}^{2}}}$

$\varepsilon_{\mathrm{r}} \times \mu_{\mathrm{r}}=\frac{\mathrm{c}^{2}}{\mathrm{v}^{2}}$

$\varepsilon_{\mathrm{r}} \times 2=\frac{\left(3 \times 10^{8}\right)^{2}}{\left(1.5 \times 10^{8}\right)^{2}}$

$\varepsilon_{\mathrm{r}} \times 2=4$

$\varepsilon_{\mathrm{r}}=2$

Answer key and solution verified before publishing.

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Exam: JEE Main 2024
Paper: 6 April, Shift 1
Subject: Physics
Chapter: Electromagnetic Waves
Topic: Properties of EM Waves and Electromagnetic Spectrum