About the light Bulb
Thomas Alva Edison is one of the most influential people of his time. Thomas Edison was born February 11, 1847 in Milan, Ohio. His inventions helped a lot of things quickly change in the world. His most famous invention was the light bulb. Thomas Edison developed a practical light bulb toward the end of 1879. This is one of his most famous inventions that we use to this day.
There are two types of light bulbs, incandescent and fluorescent. An incandescent bulb uses heat caused by an electrical current. When electrical current passes through a wire, it causes the wire to get hot. The wire gets so hot that it glows and gives off light. Today’s incandescent light bulbs have a filament made of tungsten. Since the hot tungsten would quickly burn away if it were exposed to oxygen, it must be placed in a sealed glass bulb which is either evacuated or filled with a gas that won’t let it burn.
The other common type of light is the fluorescent lamp. It is a lamp that is made of a glass tube filled with argon gas and mercury. When electrical current is passed through the gas the atoms of the gas pick up energy and radiate it in the form of ultra-violet light. The UV light then strikes the inside of the tube, which is coated with a phosphor. The phosphor glows, giving off the light. Fluorescent lamps don’t require high temperatures to produce light, like incandescent bulbs do.
