Question

The electric field `vec E` of an electromagnetic wave propagating in north direction is oscillating in up and down direction. Describe the direction of magnetic field `vec B` of the wave.

Answer 1

The electric field (E) and magnetic field (B) of an electromagnetic wave are always perpendicular to one another and the wave’s propagation direction. Given that the wave is traveling in the north direction and the electric field (E) oscillates up and down (which means along the vertical direction), the magnetic field (B) must be perpendicular to both. This indicates the magnetic field will be in the east-west direction.