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8.Electromagnetic waves
hard
In the given electromagnetic wave $E_y=600 \sin (\omega t-k x) \mathrm{Vm}^{-1}$, intensity of the associated light beam is (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
$972$
(JEE MAIN-2024)
Solution
$Intensity =\frac{1}{2} \varepsilon_0 \mathrm{E}_0^2 \mathrm{c}$
$=\frac{1}{2} \times 9 \times 10^{-12} \times(600)^2 \times 3 \times 10^8$
$=\frac{9}{2} \times 36 \times 3=486 \mathrm{w} / \mathrm{m}^2$
Standard 12
Physics
