The electromagnetic spectrum describes a wide range of different electromagnetic waves. Also called EM waves. These are a special type of wave that can travel without a medium. Unlike sound waves and water waves, electromagnetic waves don’t need a fluid. Or a solid, or even air to help them travel from one place to another. EM waves can travel across the great vacuum of space. Which is why we see light from distant stars and planets.
Electromagnetic waves are named for the fact that they have both an electric and a magnetic component. They begin when charged particles, like electrons, vibrate due to the various forces acting on them. The vibration of charged particles results in an emission of energy known as electromagnetic radiation. EM waves propagate outward from the source. Just like regular transverse waves, the oscillations of EM waves are perpendicular to the direction of the wave’s travel.
But, EM waves are more complicated; the electric component oscillates in one plane. While the magnetic component oscillates in a different plane. In a vacuum, EM waves always travel at the same speed – the speed of light. Which is roughly 300 million meters per second. We call this value the speed of light, but really. It counts as the normal speed for all of the EM waves.
So, what are the other EM waves besides light? Electromagnetic waves include infrared, ultraviolet, radio waves, and microwaves. They also include X-rays and gamma rays. You’ve probably heard of all these waves before. But you may not have seen how they relate to visible light. Let’s take a look at how these seven groups of waves fit together on the electromagnetic spectrum.