Question 59: EM waves

Question

A plane electromagnetic wave propagating in $$\mathrm{x}$$-direction is described by
$$E_y=\left(200 \mathrm{Vm}^{-1}ight) \sin \left[1.5 	imes 10^7 t-0.05 xight] 	ext {; }$$
The intensity of the wave is :
(Use $$\epsilon_0=8.85 	imes 10^{-12} \mathrm{C}^2 \mathrm{~N}^{-1} \mathrm{~m}^{-2}$$)

Accepted Answer

$$\begin{aligned}
& \mathrm{I}=\frac{1}{2} \varepsilon_0 \mathrm{E}_0^2 	imes \mathrm{c} \
& \mathrm{I}=\frac{1}{2} 	imes 8.85 	imes 10^{-12} 	imes 4 	imes 10^4 	imes 3 	imes 10^8 \
& \mathrm{I}=53.1 \mathrm{~W} / \mathrm{m}^2
\end{aligned}$$

Answer

$$35.4 \mathrm{~Wm}^{-2}$$

Answer

$$53.1 \mathrm{~Wm}^{-2}$$

Answer

$$26.6 \mathrm{~Wm}^{-2}$$

Answer

$$106.2 \mathrm{~Wm}^{-2}$$

EM waves

A plane electromagnetic wave propagating in $\mathrm{x}-direction is described by E_y=\left(200 \mathrm{Vm}^{-1}\right) \sin \left[1.5 \times 10^7 t-0.05 x\right] \text {; } The intensity of the wave is : (Use \epsilon_0=8.85 \times 10^{-12} \mathrm{C}^2 \mathrm{~N}^{-1} \mathrm{~m}^{-2}$)

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