JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
An electromagnetic wave of frequency 100 MHz propagates through a medium of conductivity, \(\sigma=10 mho / m\). The ratio of maximum conducting current density to maximum displacement current density is _________ .
\(\left[\right.\) Take \(\left.\frac{1}{4 \pi \epsilon_0}=9 \times 10^9 Nm ^2 / C ^2\right]\)
- A 1800
- B 900
- C 1000
- D 2000
Answer & Solution
Correct Answer
(A) 1800
Step-by-step Solution
Detailed explanation
\(j _{ c }=\sigma E\) \(E \Rightarrow E _0 \sin (\omega t - kx )\) \(j _{ c }=\sigma E _0 \sin (\omega t - kx )\) \(\Rightarrow\left( j _{ c }\right)_{\max }=\sigma E _0\)....(i) \(J_d \Rightarrow \frac{i_d}{A}=\frac{1}{A} \times \varepsilon_0 \frac{A d E}{d t}\)…
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