JEE Main 2021 — Electromagnetic Waves Question with Solution
From: JEE Main 2021 (Online) 24th February Evening Shift
Question
An electromagnetic wave of frequency 3 GHz enters a dielectric medium of relative electric permittivity 2.25 from vacuum. The wavelength of this wave in that medium will be _________ 102 cm.
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Show full solutionCorrect answer: 667
Correct answer
667
Step-by-step explanation
Given, frequency of wave, f = 3 GHz = 3 109 Hz
Relative permittivity, r = 2.25
Since, f = C/
m
m (wavelength of wave in a medium) = / and we know that,
As, dielectric is non-magnetic, r = 1
m
= 6.67 cm = 667 102 cm
Relative permittivity, r = 2.25
Since, f = C/
m
m (wavelength of wave in a medium) = / and we know that,
As, dielectric is non-magnetic, r = 1
m
= 6.67 cm = 667 102 cm
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