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How the light bulb works
How the light bulb works





Some of that energy isĪnd there's even a bit of sound energy produced too (in the crackling and Which a fuel (such as the wood in the logs) reacts with oxygen in theĪir to produce carbon dioxide gas, water (in the form of steam), and a When things burn, what's actually happening is a chemical reaction called But just why do hot things give off light? The discovery of fire, somewhere between one and two million yearsĪgo. People have known that hot things give off light ever since Set fire to a big bunch of logs and you'll get a nice red glow asįeeling. You can see the filament clearly as a bright white stripe in this short-exposure photograph. The filament gets red or white hot and gives off light (as well as lots of heat). Photo: An incandescent lamp makes light by passing electricity through a very thin wire filament.







How the light bulb works