Question

How do we know that light is an electromagnetic wave?

Answer 1

1. Light is a wave made of time-dependent electric and magnetic fields that generate each other so that the wave propagates.
2. In the 1860s, Scottish physicist James Clerk Maxwell unified electric and magnetic fields in his formulation of electromagnetic waves.
3. Maxwell described light as a propagating wave of electric and magnetic fields.
4. Because electromagnetic waves have to fluctuate electric and magnetic fields, they are called electromagnetic waves.
5. The speed of light is the same for all EM energy waves.
6. They always move at the same pace, regardless of their frequency or wavelength.