Light bulb – simple english wikipedia, the free encyclopedia electricity balloon experiment

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The incandescent light bulb turns electricity into light by sending the electric current through a thin wire called a filament. Filaments are made up mostly of tungsten, a metal. The resistance of the filament heats the bulb up. Eventually the filament gets so hot that it glows, producing light. [3]

The filament needs to be protected from oxygen in the air, so it is inside the bulb, and the air in the bulb is either removed (a vacuum) or more often, replaced with a gas that doesn’t affect anything, like neon or argon. Only about 3% of the energy that goes into an incandescent light bulb actually makes light, the rest makes heat. That’s one of the reasons LED’s are more efficient.

This is the type of light bulb that Thomas Edison spent so much time on in the 1870s. It was the first light bulb that could be used in houses – it did not cost too much, and it worked well. For the first time, people did not have to burn something (candles, oil lamps, kerosene lamps, etc.) to make light. It was bright enough that people could read easily at night or do work. It was used to light stores and streets, and people could travel around after dark. This started the common use of electricity in homes and businesses. Tungsten filaments, developed in the 1900s, last longer and make a brighter light. They quickly replaced carbon ones. Fluorescent light bulbs [ change | change source ]

Fluorescent lamps are efficient, and only give off ¼ the amount of heat of an incandescent. They also last longer than incandescent but until the late 20th century were much bigger and did not fit into sockets for small overhead lights and lamps like an incandescent could.

A fluorescent bulb is a glass tube usually filled with argon gas and a little bit of mercury. When turned on, the cathode heats up and sends out electrons. These hit the argon gas and the mercury. The argon gas makes a plasma which lets the electrons move around better. When the electrons hit a mercury atom it puts the molecule into a state where it has a lot of energy (stores the energy). The energetic state doesn’t last very long, and when the energy is released, it lets out a photon. Photons from mercury are not visible like some other photons; they are ultraviolet. So there’s a phosphor coating on the wall of the bulb. When the photon hits a phosphor molecule, it in turn puts that molecule into an excited state. When this phosphor releases energy, it lets out a photon that we can see, and light is made. Changing the type of phosphor can change the color we see, but usually fluorescent light bulbs are whiter than incandescent light bulbs, which are slightly yellow. LED [ change | change source ]

The incandescent light bulb turns electricity into light by sending the electric current through a thin wire called a filament. Filaments are made up mostly of tungsten, a metal. The resistance of the filament heats the bulb up. Eventually the filament gets so hot that it glows, producing light. [3]

The filament needs to be protected from oxygen in the air, so it is inside the bulb, and the air in the bulb is either removed (a vacuum) or more often, replaced with a gas that doesn’t affect anything, like neon or argon. Only about 3% of the energy that goes into an incandescent light bulb actually makes light, the rest makes heat. That’s one of the reasons LED’s are more efficient.

This is the type of light bulb that Thomas Edison spent so much time on in the 1870s. It was the first light bulb that could be used in houses – it did not cost too much, and it worked well. For the first time, people did not have to burn something (candles, oil lamps, kerosene lamps, etc.) to make light. It was bright enough that people could read easily at night or do work. It was used to light stores and streets, and people could travel around after dark. This started the common use of electricity in homes and businesses. Tungsten filaments, developed in the 1900s, last longer and make a brighter light. They quickly replaced carbon ones. Fluorescent light bulbs [ change | change source ]

Fluorescent lamps are efficient, and only give off ¼ the amount of heat of an incandescent. They also last longer than incandescent but until the late 20th century were much bigger and did not fit into sockets for small overhead lights and lamps like an incandescent could.

A fluorescent bulb is a glass tube usually filled with argon gas and a little bit of mercury. When turned on, the cathode heats up and sends out electrons. These hit the argon gas and the mercury. The argon gas makes a plasma which lets the electrons move around better. When the electrons hit a mercury atom it puts the molecule into a state where it has a lot of energy (stores the energy). The energetic state doesn’t last very long, and when the energy is released, it lets out a photon. Photons from mercury are not visible like some other photons; they are ultraviolet. So there’s a phosphor coating on the wall of the bulb. When the photon hits a phosphor molecule, it in turn puts that molecule into an excited state. When this phosphor releases energy, it lets out a photon that we can see, and light is made. Changing the type of phosphor can change the color we see, but usually fluorescent light bulbs are whiter than incandescent light bulbs, which are slightly yellow. LED [ change | change source ]