Incandescent Light Bulb
Edison started working on the incandescent light bulb right after he finished the phonograph. Many people think that Edison was the one to invent the light bulb. That is not true, Edison just profected a 50 year old idea. In 1809, Humphry Davy invented the first electric light by connecting wires and a piece of carbon to a battery. Then, there was 21 other people who tried to make the light bulb using Humphry Davy's idea, but Edison perfected the idea. Edison said it was he hardest thing to invent, and he had to study the hardest to make it work.
Edison created his version of the incandescent light bulb in 1879. He used electricity, a filament, and an improved and very strong vacuum. The filament is the part in the light bulb that glows. If the filament breaks, then the bulb will burn out. So, the filament is a very crucial part in the light bulb. Thomas Edison took his time in finding the right filament that would burn for the longest time period. He experimented with over a thousand filaments, but he finally got one to work. Next, he needed a good vacuum inside of the globe. The vacuum's job is to keep the filament burning. Hot air hits the filament, causing it to oxidize. It can reach temperatures between 3,600 and 4,600 degrees fahrenheit. If it becomes too hot, then it will become very weak, and might break. The vacuum lets the filament burn longer by keeping it from oxidizing too quickly. With his combination of the carbon filament and the strong vacuum, the light bulb burned for 40 hours in the globe. Then he experimented with it some more, and found out that if you changed the shape of the filament into a horseshoe, it burned for 100 hours. Then, with additional improvements, he got it to burn for 1500 hours.
The incandescent light bulb helped us out so much and in so many ways. The first way is that people could now work longer hours. It usually got dark around 5 or 6, then people had to stop working. But the incandescent light bulb gave people light, so if they needed to work later, it could now be possible. Another way it helped was with workplace safty. People often worked when it was dark out, which is very dangerous. They might of had candles going, but that did not do that much. The incandescent light bulb made everything brighter, causing less accidents, making work much safer. It also helped with home safety. Mostly everybody burned candles or oil lamps, which is a very dangerous fire hazard. A lot of houses burnt down because of that. But with the incandescent light bulb, it enabled you to see, without the dangerous fire hazards. The last thing it helped with was home Leisure activities. Many people got home and it was dark, which meant they couldn't really do anything. But the lightbulb helped people see, enabling them to do a variety of more things. The light bulb was very helpful back then, and still is today. We are still using the light bulb today, which means we have been using the light bulb for over 130 years. We wouldn't of gotten this far in life without the light bulb.
http://www.juliantrubin.com/bigten/bulbexperiment.html
http://www.edinformatics.com/inventions_inventors/incandescent_light_bulb.htm
http://www.ideafinder.com/history/inventions/lightbulb.htm
http://www.enotes.com/how-products-encyclopedia/light-bulb
http://invsee.asu.edu/Modules/lightbulb/meathist.htm
http://www.edinformatics.com/inventions_inventors/incandescent_light_bulb.htm
http://www.ideafinder.com/history/inventions/lightbulb.htm
http://www.enotes.com/how-products-encyclopedia/light-bulb
http://invsee.asu.edu/Modules/lightbulb/meathist.htm
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