A lamp emits monochromatic green light uniformly in all directions . The lamp is $\;3 \%\;$ efficient in converting electrical power to electromangetic waves and consumes 100 W of power .The amplitude of the electric filed associated with the electromagnetic radiation at a distance of 5 m from the lamp will be nearly :

Question

$(a)\;1.34\;V/m \qquad(b)\;2.68\;V/m \qquad(c)\;4.02\;V/m \qquad(d)\;5.36\;V/m$