What is the relationship between the electric and magnetic fields in a plane electromagnetic wave?

In a plane electromagnetic wave, the electric field and magnetic field are closely linked and work together to carry energy through space.

Simple Explanation:

• The electric field (E) and the magnetic field (B) are:
  • At right angles to each other (perpendicular),
  • And both are perpendicular to the direction the wave is traveling.

This means the wave has a three-directional structure:

1. Electric field → Up/down (say, vertical)
2. Magnetic field → Left/right (say, horizontal)
3. Wave travels → Forward (say, into the screen)

Key Points:

• The electric and magnetic fields oscillate (vibrate) as the wave moves.
• They are always in phase (reach maximum and minimum values together).
• The changing electric field creates the magnetic field, and vice versa.
• Together, they allow the wave to move forward — even through empty space.