MCQ
In an electromagnetic wave, the electric magnetising fields are $\frac{100\text{V}}{\text{m}}$ and $\frac{0.265\text{A}}{\text{m}}$ The maximum energy flow is?
  • $\frac{26.5\text{W}}{\text{m}^2}$
  • B
    $\frac{36.5\text{W}}{\text{m}^2}$
  • C
    $\frac{46.7\text{W}}{\text{m}^2}$
  • D
    $\frac{765\text{W}}{\text{m}^2}$

Answer

Correct option: A.
$\frac{26.5\text{W}}{\text{m}^2}$

Maximum rate of energy flow, $S = E _0 \times H _0$
Given, $\text{E}_0=\frac{100\text{V}}{\text{m}},\text{H}_0=\frac{0.265\text{A}}{\text{m}}$
$\therefore\text{S}=100\times0.265=\frac{26.5\text{W}}{\text{m}^2}$​

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