During some sporting events, the atmosphere is always electric: the World Cup of soccer, game 7 of the World Series, the Superbowl. In these events, some people like to do the wave: a mass of people rising and falling one after another, creating a pattern all the way around the stadium. While it might not be a real wave, it does share a lot in common with one. Like a real wave, it’s a repeating pattern of peaks and troughs. And like a real wave, it involves energy moving from one place to another (in this case human energy – excitement is contagious!). It also reminds us that waves can be made out of different materials: a wave of people, a water wave, a sound wave in the air, or a light wave traveling through space.
Waves and optics is about understanding those waves and how they work. It involves learning the features and properties of waves: that waves have crests, troughs, wavelengths, frequencies, amplitudes, speeds, and time periods. It’s about learning how waves operate in different materials, and how they interfere with each other.
Optics is the study of light waves, because light is special. In the bible, God didn’t say, “Let there be cream cheese!” Although we would still be pretty impressed if he had. For humans, sight is probably the most important sense we have, so it’s definitely special to humans. But more importantly, light waves are the only kinds of waves that can travel through the vacuum of space. Which is a good thing, because we would freeze to death without the waves the Sun produces.
Optics is about how light waves reflect, bend, and spread out. It explains how our reading glasses bend light to improve our sight, and how telescopes and microscopes work. And what would life be without rainbows? Especially double rainbows all the way across the sky.