WEBVTT

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I got a right to sing the blues. I got a right to

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moan inside. I got a right to sit and cry

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down around the river.

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I love boxes.

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Whoa, what's that music?

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Oh, that's just Billie.

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Oh no, she sounds pretty sad.

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Yeah, don't go nuts. Billie's just got the blues again.

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[unclear reply]

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Hey, Billie, why are you so blue?

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I suppose that's just the way I am.

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So you've always been blue?

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Yeah, well, she's made with gallium nitride.

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Gallium what?

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Wait, what are you talking about?

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Well, Adabot, inside every LED is a small crystal.

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Really?

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When you connect the short leg of an LED to ground

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and the longer leg to positive voltage, voila!

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The crystal glows and the LED lights up.

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Very cool.

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So, electricity flowing through an LED's crystal creates light.

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But why are LEDs certain colors in the first place?

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The type of crystal used in an LED determines that LED's color.

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Oh, interesting.

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A red LED like me uses a type of crystal made of gallium arsenide.

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That's two elements, gallium and arsenic mixed together.

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I use an aluminum gallium crystal to get so green.

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And indium gallium nitride is what makes me so blue.

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oh so different crystals make different colored light

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but I've also seen LEDs

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that change color how do they do that well we usually call those color

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changing LEDs RGB LEDs hey I've got an RGB LED

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right here

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oh good let's take a closer look to see how they work

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we call them RGB because

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Because inside every one of them are three different types of crystals.

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One that makes red light, one that makes green light, and one that makes blue.

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I get it. RGB. Red, green, and blue.

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Exactly! And by mixing red, green, and blue, we can make pretty much any color we want.

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Like, say, purple.

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Or orange.

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Or even white.

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Wow. Thanks, guys.

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LEDs make a lot more sense now.

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You're very welcome, Adabot.

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LEDs are in so many electronic devices,

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screens, billboards,

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even light bulbs.

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Yeah. It's really important to understand how they work.

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Agreed.

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You know, Billie,

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you may be blue,

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but you light up my life.

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Awwww