JEE Main 2021 — Electromagnetic Waves Question with Solution
From: JEE Main 2021 (Online) 24th February Morning Shift
Question
An electromagnetic wave of frequency 5 GHz, is travelling in a medium whose relative electric permittivity and relative magnetic permeability both are 2. Its velocity in this medium is ____________ 107 m/s.
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Show full solutionCorrect answer: 15
Correct answer
15
Step-by-step explanation
Given, r = r = 2
where, r is relative permeability, r is relative permittivity.
Speed of electromagnetic wave v is given by
where, n = refractive index =
= 15 107 m/s
x 107 = 15 107
x = 15
where, r is relative permeability, r is relative permittivity.
Speed of electromagnetic wave v is given by
where, n = refractive index =
= 15 107 m/s
x 107 = 15 107
x = 15
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