For an electromagnetic wave propagating through vacuum, k represents the propagation vector, E represents the electric-field vector and ω is the angular frequency. Which expression represents the magnetic-field vector B associated with the wave?
Options

Question

For an electromagnetic wave propagating through vacuum, k represents the propagation vector, E represents the electric-field vector and ω is the angular frequency. Which expression represents the magnetic-field vector B associated with the wave?

Options

G1 Physics · Accepted Answer

For a plane electromagnetic wave in vacuum, k×E = ωB. Therefore, B = (k×E) ÷ ω. The direction also follows the right-hand rule: E, B and the propagation direction form a mutually perpendicular triad. Correct option: B.