JEE Main 2021 — Electromagnetic 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
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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