JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
In the given electromagnetic wave \(E_y=600 \sin (\omega t-k x) \mathrm{Vm}^{-1}\), intensity of the associated light beam is what? (in \(\mathrm{W} / \mathrm{m}^2\) ); (Given \(\epsilon_0=\) \(\left.9 \times 10^{-12} \mathrm{C}^{-2} \mathrm{~N}^{-1} \mathrm{~m}^{-2}\right)\)
- A \(486\)
- B \(243\)
- C \(729\)
- D \(972\)
Answer & Solution
Correct Answer
(A) \(486\)
Step-by-step Solution
Detailed explanation
\(Intensity =\frac{1}{2} \varepsilon_0 \mathrm{E}_0^2 \mathrm{c}\) \(=\frac{1}{2} \times 9 \times 10^{-12} \times(600)^2 \times 3 \times 10^8\) \(=\frac{9}{2} \times 36 \times 3=486 \mathrm{w} / \mathrm{m}^2\)
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