JEE Main 2018PhysicsElectromagnetic WavesEasyMCQ

JEE Main 2018 — Electromagnetic Waves Question with Solution

JEE Main 2018 (08 Apr)

Question

An EM wave from air enters a medium. The electric fields are E→1=E01x^cos⁡2πvzc-t  in air and E→2=E02x^cos⁡k2z-ctin medium, where the wave number k and frequency v refer to their values in the air. The medium is non-magnetic. If ϵr1 and ϵr2 refer to relative permittivities of air and medium respectively, which of the following options, is correct?

Choose an option

Show full solutionCorrect option: D
Correct answer
Dϵr1ϵr2 =14

Step-by-step explanation

∨air∨med=cc/2=2=μ0ϵ0μr2ϵr2μ0ϵ0μr1ϵr1 

ϵr1ϵr2=14

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About this question

This is a previous-year question from JEE Main 2018, 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.