Science Behind Lightbulb

What’s the science behind light?
A lightbulb is “a glass bulb inserted into a lamp or a socket in a ceiling, that provides light by passing an electric current through a filament or a pocket of inert gas.” ("Light Bulb - Definition of Light Bulb in English | Oxford Dictionaries") Light is a form of energy emitted by an atom. Light is made up of many light photons, which are small particles that have energy and momentum but no mass. Atoms release photons when the electrons become “excited” and then return to their original orbital. The colour of the light is dependent upon the wavelength of the emitted light, which is dependent upon how much energy is released. The energy released is dependent upon what energy level the electron had before being
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The first portion of the lightbulb is the base, which is a brass or aluminum component where electrical contact is made. There is one lead-in wire that is soldered or welded to the rim of the base interior. The other lead-in wire is soldered to the center contact. The two portions are insulted from each other by a glass insulator, which appears as a black ring around the center contact. The next component is the steam press. The lead-in wires in the glass lightbulb have an air tight seal in the steam press. At this point the wires are made out of a nickel-iron alloy core and a copper sleeve to assure that the wires have the same coefficient of expansion as the glass. This is because the size of the glass bulb will change in accordance with the change in temperature. To make sure the wires also expand by roughly the same amount, the same coefficient is needed. Next, the glass bulb itself is typically made of soft glass. Hard glass is used only when the bulb needs to withstand higher temperatures and for added protection against the bulb breaking due to any moisture. They can be molded into multiple shapes and finishes. The fourth component is the button. To make this part glass is heated during manufacturing. Support and tie wires are placed into it. The lead-in wires are used to carry current from the socket to the filaments in the bulb. They are usually made of copper from the base to the stem press and then nickel-plated copper of …show more content…
An electric current is the mass migration of electrons that do not have strong bonds with an atom from a negatively charged area to a positively charged area. As the current travels along through the filament, the free electrons are constantly collding into the molecules that make up the filament. The energy of each collision causes the atoms to heat up, which is due to the electrons being excited. A thinner conductor is less resistant to the movement of electrons and would therefore heat up more quickly versus a thicker conductor. As previously stated, when these excited electrons fall back to their normal levels, the electrons release the extra energy in the form of photons. Metal atoms tend to release infrared light photons, which are invisible to the human eye. However, once the atoms are heated to around 2,200 degrees celsius, they will release visible light. The tungsten is arranged in a double coil in order to fit it all in a small space. That is, the filament is wound up to make one coil, and then this coil is wound to make a larger coil. Tungsten is used in nearly all incandescent light bulbs because it is an ideal filament material. Most metals will actually melt before reaching 2,200 degree celsius because the vibrations will break apart the bonds between the atoms so that the material becomes a liquid. However, tungsten has

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