JEE Main 2021PhysicsElectromagnetic WavesDisplacement Current And Properties Of Em WavesmediumNumerical

JEE Main 2021Electromagnetic Waves Question with Solution

From: JEE Main 2021 (Online) 17th March Evening Shift

Question

Seawater at a frequency f = 9 102 Hz, has permittivity = 800 and resistivity = 0.25 m. Imagine a parallel plate capacitor is immersed in seawater and is driven by an alternating voltage source V(t) = V0 sin(2ft). Then the conduction current density becomes 10x times the displacement current density after time t = s. The value of x is _____________. (Given : Nm2C2)

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Show full solutionCorrect answer: 6
Correct answer
6

Step-by-step explanation

JEE Main 2021 (Online) 17th March Evening Shift Physics - Electromagnetic Waves Question 85 English Explanation
Given f = 9 102 Hz

= 0r

= 80 0

So r = 80

= 0.25 m

V(t) = V0 sin (2ft)





.......... (1)

&

....... (2)

divide equation (1) and (2)













So x = 6

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About this question

This is a previous-year question from JEE Main 2021, 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.