JEE Main 2026 — Electromagnetic Waves Question with Solution
JEE Main 2026 (28 January Shift 1)
Question
The electric field of an electromagnetic wave travelling through a medium is given by
then the refractive index of the medium is .
(All given measurement are in SI units)
then the refractive index of the medium is .
(All given measurement are in SI units)
Choose an option
Show full solutionCorrect option: A
Correct answer
A1.5
Step-by-step explanation
The electric field is V/m.
This is in the standard form where angular frequency rad/s and wave number rad/m.
The speed of the wave in the medium is m/s.
The refractive index is defined as where m/s is the speed of light in vacuum.
Therefore,
This is in the standard form where angular frequency rad/s and wave number rad/m.
The speed of the wave in the medium is m/s.
The refractive index is defined as where m/s is the speed of light in vacuum.
Therefore,
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This is a previous-year question from JEE Main 2026, covering the Electromagnetic Waves chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.