A Plane Electromagnetic Wave Propagates in a Vacuum in the Z-Direction

Multiple Choice

A plane electromagnetic wave propagates in a vacuum in the z-direction. The wave has a wavelength of 10 m and the electric field is along the +x direction and has an amplitude of is 0.20 V/m, with one maximum at x = 0 and t = 0. What is the mathematical expression for the magnetic field?

A) B_y = 0.067 × 10^-8sin[(0.63 m^-1) z - (2.1 × 10^-9 s^-1) t] T
B) B_y = 0.067 × 10^-8sin[(0.63 m^-1) z + (2.1 × 10^-9 s^-1) t] T
C) B_y = 0.067 × 10^-8cos[(0.63 m^-1) z + (1.9 × 10⁸ s^-1) t] T
D) B_y = 0.067 × 10^-8cos[(10 m^-1) z - (2.1 × 10^-9 s^-1) t] T
E) B_y = 0.067 × 10^-8cos[(0.63 m^-1) z - (1.9 × 10^-8 s^-1) t] T