An electrical current passes from one metal contact to the other when a light bulb is connected to an electrical power supply. The filament warms up as the current flows between the wires and the filament, causing it to emit photons, which are little packets of visible light. The photons travel through space until they reach something that reflects them back towards the filament, where they are absorbed again. This repeated process gives off the light we see from a light bulb.
The physics behind how light bulbs work was discovered by Michael Faraday in 1831 and Joseph Albert Langevin in 1872. They both won Nobel prizes for their discoveries.
Before we talk about how light bulbs work, let's go over some basic terminology. The word "bulb" is used to describe any incandescent or fluorescent lamp. Edison invented the light bulb as we know it today and he patented it in 1903. Since then, many different manufacturers have come up with their own versions of the light bulb, some more successful than others.
The phrase "light bulb era" is used to describe the period in history when the majority of homes were equipped with light bulbs. This began in the early 20th century and ended around 1980. Since then, many different types of lighting have been developed and many more are being created all the time. Today, nearly every home in America is equipped with at least one form of electric light fixture.
An electric current is carried through a thin metal filament in an incandescent bulb, heating it till it glows and creates light. After passing through the tungsten filament, the energy travels down another wire and out of the bulb via the metal piece on the side of the socket. This is called an external circuit because the filament is part of it; the other part goes into the body of the bulb and makes it functional. The filament needs to be heated to about 3000 degrees Celsius (5692 F) for its coating of phosphorous oxide to evaporate completely, otherwise it will just burn off again during usage.
What happens if you use a regular bulb instead of an Edison bulb? They both operate using the same principle - but a carbon filament inside a glass tube heats up when electricity passes through it, which causes it to emit light. An ordinary bulb uses about 1/10th the power as an Edison bulb and they last about 10 times as long. But they are much less efficient at converting electrical energy into light, so to get the same amount of light from an ordinary bulb as from an Edison bulb, you need more than twice as many ordinary bulbs as Edison bulbs.
In conclusion, light bulbs work by using resistance to heat up a filament, which then emits light.
When a current flows across a wire, electrical energy is converted to heat, which causes the wire to become incredibly hot—nearly 1000 oF! Objects this heated emit visible light, and there you have your light bulb.
The most common type of light bulb is the incandescent lamp, which uses electric resistance inside the filament to produce heat that emits light. The Edison light bulb was an improvement upon the incandescent lamp, with its carbon filament being heated by direct passage of current from the battery rather than through a resistive element. Modern lamps still use some form of filament technology to create light, but now power is passed directly into the filament instead. These include fluorescent, halogen, and solid-state lights.
Electricity is the flow of electrons through a conductor such as a copper wire. When these electrons move through matter they can cause atoms to vibrate, which is how we get sound waves in loud speakers and music notes on a piano keyboard. But electrons don't touch atoms directly, so they must travel through other particles to do work. For example, when an electron moves through a piece of wire it may cause nearby atoms to vibrate, but it cannot leave the wire because it is bound to the atom it moved. Instead, it triggers another electron to come away from somewhere else on the atom and move to the empty spot where the first electron went.
The incandescent light bulb converts energy into light by passing it via a tiny wire known as a filament. The majority of electrical filaments are constructed of tungsten metal. The filament's resistance warms the bulb. Light is emitted when the filament becomes hot enough to emit electrons that travel toward Earth instead of away from it.
Some filaments are made of carbon compounds such as graphite or charcoal. These do not burn out like regular filaments do but rather become incandescent over time. They require more attention because they can break down under heat or humidity, which could lead to exposure to dangerous gases.
There are also fluorescent lights. These use electricity to excite mercury vapor inside glass tubes. The excited atoms produce visible light as they decay back into their original state. This type of light has been used in homes and businesses for many years now, but it does have some disadvantages. First, it contains hazardous materials that must be handled carefully. Second, it tends to be less bright than an ordinary light bulb. But most important, it lasts much longer! Regular light bulbs have their lifespan limited by the strength of the filament temperature. But since fluorescent bulbs operate at lower temperatures, they can last for decades if not treated harshly.
Light bulbs work because electricity passes through them when they get hot enough.