JEE Main 2026 — Electromagnetic Waves Question with Solution
JEE Main 2026 (23 January Shift 2)
Question
The ratio of speeds of electromagnetic waves in vacuum and a medium, having dielectric constant and permeability of , is
( permeability of vacuum)
( permeability of vacuum)
Choose an option
Show full solutionCorrect option: D
Correct answer
D
Step-by-step explanation
Speed of electromagnetic wave in vacuum:
Speed in a medium with permeability and dielectric constant :
Ratio of speeds:
Therefore:
Speed in a medium with permeability and dielectric constant :
Ratio of speeds:
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.