JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
The electromagnetic waves travel in a medium at a speed of \(2.0 \times 10^{8}\, m / s\). The relative permeability of the medium is \(1.0.\) The relative permittivity of the medium will be
- A \(2.25\)
- B \(4.25\)
- C \(6.25\)
- D \(8.25\)
Answer & Solution
Correct Answer
(A) \(2.25\)
Step-by-step Solution
Detailed explanation
\(V =2 \times 10^{8} m / s\) \(C =3 \times 10^{8} m / s\) \(\frac{ C }{ V }=\sqrt{\mu_{ r } \in_{ I }}\) \(\frac{9}{4}=1 \times \epsilon_{ r }\) \(\epsilon_{ I }=\frac{9}{4}=2.25\)
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