JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
The energy of an electromagnetic wave contained in a small volume oscillates with
- A zero frequency
- B half the frequency of the wave
- C double the frequency of the wave
- D the frequency of the wave
Answer & Solution
Correct Answer
(C) double the frequency of the wave
Step-by-step Solution
Detailed explanation
\(E=E_0 \sin (\omega t-k x)\) Energy density \(\left(\frac{d u}{d v}\right)=\varepsilon_0 E_0^2 \sin ^2(\omega t-k x)\) \(\frac{\varepsilon_0 E _0^2}{2}[1-\cos (2 \omega t -2 kx )]\)
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