Green Flash - Back 'EMF' by MIT Physics Demo

[Jules Tresor]

Hey guys,
I just found this short video by MIT Tech TV Youtube channel:

YouTube - MIT Physics Demo -- Back "emf" in a Large Solenoid

They charge a large coil, up to 30A, and open the switch by hand, and we can see an enormous flash of light, that starts as GREEEEEN, like the one we are looking for in Gray's systems after Aaron discovery of how to make it easily.
MDG

[cody]

Wow! Our most briliant brains at MIT are calling that effect back emf. So smart, yet they still have so much to learn

[Jules Tresor]

You are right man

Yes cody, the MIT engineers should come and spend a few hours learning on Energetic forum to see the real stuff they have no idea they could play with

[Sephiroth]

lol... well we all know MIT can't even build an SSG

[lighty]

One should really learn to respect other schools of thought even if they make some apparent mistakes. I don't laugh on all of the rubbish "forum experts" write when they suppose they understand basic EE and basic physics. Also MIT is a vast establishment and I doubt that youtube video clip is a representative of all the people working there.

BTW- the spark is green because of the copper burning when arc is established. It's nothing special and it's been known for well over a hundred years. If they were to replace contactor material with some other metal and if oxidizing and melting point of that material is low enough you would see other colours.

[Jbignes5]

yup I agree.

You got that right Lighty. It is the oxidized copper burning that makes the start with a green flash. You also point out what has held this community back and the "other community" from going forward. This isn't a competition. They only sought to show that back emf is the main reason for the flash.