: why does a flame give off light?
In: Physics
This takes a few key concepts that we’ll string together.
What makes light, at all.
All light comes from when an object with charge is “accelerated”. Bounce, bump, shake, speed up, spin etc, a charged object and it creates a wave in the electromagnetic field. We call this light.
Atoms have a charge, specifically the electrons that are bound to them. So if you shake and bounce atoms enough, you can create light.
Fire is a chemical reaction. The oxygen in the air reacts with the molecules of the item “burning”. This means it slams into the molecules, and snaps them into smaller parts that go flying off like debris in any collision.
Because these molecules and pieces got slammed into so hard, the electrons shake, and release light.
A lightbulb works in a similar way. Except instead of oxygen slamming into molecules we run electricity through the bulb, a river of flowing electrons that bump and shake the atoms of the filament as they pass by.
LED’s are also similar, except they work more like making the river of electrons make the light itself. The LED essentially is a stair step “waterfall” or “electricity-fall” and as the electrons fall over the edge, they bump and release light at the bottom.
Radio and Cell-phone antennae do this too. They pass electricity back and forth along the wire that is antenna. This shaking of the electrons create the radio “light” that other devices pick up.
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