A point source of $100\,W$ emits light with $5 \%$ efficiency. At a distance of $5\,m$ from the source, the intensity produced by the electric field component is :
A point source of $100\,W$ emits light with $5 \%$ efficiency. At a distance of $5\,m$ from the source, the intensity produced by the electric field component is :
- [JEE MAIN 2023]
- A
$\frac{1}{2 \pi} \frac{ W }{ m ^2}$
- B
$\frac{1}{40 \pi} \frac{ W }{ m ^2}$
- C
$\frac{1}{10 \pi} \frac{W}{ m ^2}$
- D
$\frac{1}{20 \pi} \frac{ W }{ m ^2}$
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