Light Is a Wave of Fields

Electric and magnetic, together

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Changing electric and magnetic fields create each other and travel as a wave.
• EM waves are transverse: E and B are perpendicular to each other and to the direction of travel.
• All EM waves move at $c = 1/\sqrt{\mu_0\varepsilon_0} \approx 3.00 \times 10^8$ m/s in vacuum.

Steps

1. A self-sustaining wave
2. An electromagnetic wave
3. The magnetic part
4. Shake a charge
5. No medium needed
6. Maxwell’s calculation