Question

For the plane electromagnetic wave given by $E = E_o sin (ωt-kx)$ and $B = B_o sin ( ωt-kx)$, the ratio of average electric energy density to average magnetic energy density is

• A. 2
• B. 1/2
• C. 1
• D. 4

Answer 1

Answer: (C)

1

Answer 2

In EM waves, average electric energy density is equal to average magnetic energy density.
1/ 4 𝜖_0𝐸_0^2 = 1/4𝜇_0 𝐵_0