it goes just as fast as an infra red wave goes, as ultra violet wave, gamma ray, all the electromagnetic waves. guess what we'll gonna be talking about later in the course, gang? electromagnetic waves, they all have the same speed, that's 300,000 kilometers per second. in fact, for light, we say it's a constant, so we say, c. c for constant, that's 300,000 kilometers per second. and that's equal to the frequency of the wave multiplied by its wavelength. questions? what is the label for the--for-- to... say, again? the label for each, it has to be a certain thing, right? like for your distance, shouldn't it not be-- on labeled in meters or something? oh, yeah. if this is in meters, and this is in seconds then i get meters per second. and i'll have my speed in meters per second. it turns out, for a light wave, you go a hundred--you go 300,000 kilometers in one second. so you'll have distance and meter or kilometers or micrometers, or miles, yeah, and t and some unit of time. could be like days, huh, or could be hours talk about miles per hour, meters per second, all those thing. but the un

and then beyond the x-rays, you get what's called gamma rays. but there's a whole smish-smash of waves, okay? less than 1% we can see, and we call that light. here, gang, i have a prism, all right. this is a prism brought in by roger, okay? this is a roger prism, all right? and this prism will also take the light and bend it into a rainbow. later, we're gonna take some white light shining in here, and, boom, you're gonna see on the other side, what? begin with r and with b. - rainbow. - a rainbow. and that rainbow is another word for spectral-- spectrum of colors, yeah? and this will give us spectrum of colors too. it turns out it will give a spectrum of colors because it turns out different colors of light will travel at different speeds-- right. --through this material or any material. did you guys know the speed of light is less in glass and water than it is in air? and how come the light slows down when it gets to the glass or when it gets to the water or anything? and here's another thing. this used to bother me years ago. if the light slow