COMEDK · Physics · 24. Electromagnetic Waves
Electromagnetic waves travel in a medium with a speed of \(2 \times 10^8 \mathrm{~ms}^{-1}\). The relative permeability of the medium is 1 . The value of relative permittivity of medium is
- A 1.95
- B 7.21
- C 3.36
- D 2.25
Answer & Solution
Correct Answer
(D) 2.25
Step-by-step Solution
Detailed explanation
Given, \(v=2 \times 10^8 \mathrm{~ms}^{-1}\) and \(\mu_r=1\) The speed of EM waves in a medium is given by \(v=\frac{1}{\sqrt{\mu \varepsilon}}\)...(i) where, \(\mu\) and \(\varepsilon\) are absolute permeability and absolute perimittivity of the medium. Now, \(\mu=\mu_0 \mu_r\)…
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