Science Common Sense

1701 - What is the relationship between the electric field, magnetic field, and direction of propagation of a plane electromagnetic wave?

Imagine you're at the beach, watching the waves. A plane electromagnetic wave is like a big ocean wave, but instead of water, it's made of electric and magnetic fields moving through space.

In this wave, there are three things that are important to know:

1. Electric field (E): It's like a line of ducks swimming in one direction.
2. Magnetic field (B): It's like another line of ducks swimming in a different direction, but always at a right angle (90°) to the electric field ducks.
3. Direction of propagation: This is like the direction the wave is moving through the ocean, or in this case, through space.

Here's how they are related:

• The electric field (E) and magnetic field (B) are always at a right angle (90°) to each other.
• The direction of propagation is also at a right angle to both the electric and magnetic fields.
• If you point your thumb in the direction of the electric field (E), your fingers will point in the direction of the magnetic field (B), and your palm will point in the direction of propagation.

This relationship is called the right-hand rule, and it helps us understand how the electric and magnetic fields work together in an electromagnetic wave.