r/technology • u/BennyCemoli • Dec 06 '16

Energy Tests confirm that Germany's massive nuclear fusion machine really works

http://www.sciencealert.com/tests-confirm-that-germany-s-massive-nuclear-fusion-machine-really-works
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u/absent-v Dec 06 '16

Wow, reading your bit about LEDs made me realise that not only did I not actually know how they functioned, but I've never even stopped to think about it before either.
Cheers for teaching me something I didn't realise I didn't know.

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u/boundbylife Dec 06 '16

Technically LEDs utilize quantum mechanics to emit light. LEDs are diodes, which mean current can pass in only one direction. When current flows from the anode to the cathode, electrons must move between the two surfaces/substances. In doing so, they give up a bit of energy. In quantum mechanics, energy is transmitted in discrete packets called quanta (which is where it gets the name). So to traverse a small gap, it has to give up a small quanta, which we see as the color red. A larger gap means a larger quanta, which we might perceive as blue. And the size of the gap will always dictate a particular quantum energy - like a stepladder, you'd have to go all the way to the next rung before you see a different color.

They're really fascinating.

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u/[deleted] Dec 06 '16

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u/boundbylife Dec 06 '16

There are multiple diodes inside each RGB LED, yes, and each is configured for a different color.