JEE PHYSICS MCQ: ELECTROMAGNETIC WAVES

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Application +4 | -1

The electric field of an electromagnetic wave is given by

E=100 \sin \omega\left(t-\frac{x}{v}\right) N / C.

Find the energy contained in a hypothetical space of volume

100 \mathrm{~cm}^3

(Given

\left.\epsilon_0=9 \times 10^{-12} C^2 N^{-1} m^{-2}\right)

View answer and explanation

Correct option: C

2.25 \times 10^{-12} \mathrm{~J}

Option C (

2.25 \times 10^{-12} \mathrm{~J}

) is correct because the energy density of an electromagnetic wave is proportional to the square of the electric field, and the energy is the energy density times the volume.

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