Which statement can correctly describe a plane electromagnetic wave in vacuum?

Question

G1 Physics · Accepted Answer

A plane electromagnetic wave in vacuum is transverse. Therefore E and B are mutually perpendicular and both are perpendicular to the propagation direction. Their amplitudes satisfy E₀/B₀ = c, or E₀ = cB₀. They also oscillate in phase: when E is maximum, B is maximum at the same point and time. Therefore option B is correct.