For an electromagnetic wave, E ⃗ \vec{E} E =E₀(4î-3ĵ)cos(ωt-kz). Which magnetic field is correct?

Question

G1 Physics · Accepted Answer

E⃗ and B⃗ are in phase, perpendicular, and E⃗×B⃗ points along +k̂. A vector perpendicular to (4î-3ĵ) that gives +z propagation is (3î+4ĵ). Also |B|=|E|/c, giving the stated option.