ITUFSD

ITUFSD

Friday, January 8, 2016

Science Column: What’s Light?

Science Column: What’s Light?
By Sheryl Lin

Have you ever wondered what light really is? It might be something that we take for granted, that we’re able to see the world around us. But take a deeper look, and you might learn something new.

There are these things known as electromagnetic waves. What are they? Well, examples of electromagnetic waves would include x-rays, radio and TV waves, and light. Normally, in science, a wave is a ripple going through some kind of medium - think of a wave in a lake. Water is an example of a medium, and so is air. Most waves need a medium. Electromagnetic waves, however, don’t need one.

Light is a type of electromagnetic wave. It’s the only kind that we can see. Light turns out to be the most abundant type of electromagnetic energy that the sun produces, and it’s also the best at going through water. Most other waves, like UV rays and infrared waves are absorbed instead. The funny thing is, since light is basically the same as all other types of electromagnetic waves, if you could see ultraviolet light the ocean would be the color of ultraviolet!

Now, what makes something the color that it is? Basically, all materials absorb a certain color of light and reflect other colors. When a color is absorbed, you can’t see it, and when a color is reflected you can. So something that’s green would absorb all colors but green, and something that’s red would absorb all colors but red. Black things absorb all light, and white things absorb very little.

Isn’t light cool? Things like this are taught in high school level classes, so now you’ve learned something new!