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METHODS OF LIGHT PRODUCTION: :bulb::zap: - Coggle Diagram
METHODS OF LIGHT PRODUCTION:
:bulb::zap:
INCANDESCENCE:
EX. Traditional light bulb AKA Incandescent Light bulb; When the bulb is connected to an electrical power supply the electrical current flows from one metal contact to another. As the current travels through, the filament heats up and it begins to emit photons, thus creating light.
A typical light bulb is has a Tungsten Filament. However, not all metals will create light that is visible to the eye when heated to extreme temperatures as some might melt. However, an inert gas is added to the lightbulb to prevent the tungsten from catching on fire and to prevent the tungsten atoms from evaporating.
When light is fed off of living organisms as the resulted of a chemical
ELECTRIC CHARGE:
Electric discharge is the process of when light is passed through electric currents using gas.
Neon lights are created through electric discharge
PHOSPHORESCENCE:
When light is created by absorbed UV light allowing an emission of visible light over an extended period of time.
Glow in the dark toys have substances called phosphors that help give off visible light after being energized.
FLUORESCENCE:
The production of visible light through the absorbption of UV light.
Fluorescent chemicals absorb light from the ultraviolet spectrum. When molecules absorb this light they release most of the energy in the form of visible light while the rest is released in the form of heat. Fluorescent objects are giving back more energy than they initially receive giving them a vibrant and gleaming appearance.
Highlighters are an example of Flourescence objects
CHEMILUMINESCENCE:
Chemiluminescence is the production of light from the result of a chemical reaction.
EX. Luminol creates visible light when it reacts with an oxidizing agent. Forensic scientists use the reaction of luminol to detect blood at crimes. A mixture of the substance and hydrogen peroxide solution is prayed to the area where they may be blood and if there is blood a blue glow will appear. However, the room must be completely dark.
EX. Glowsticks begin to flow after being snaped or shaken. Glowsticks contain a mixture of diphenyl oxalate and dye and a smaller tube of hydrogen peroxide inside as well. When the tube has snapped the glass inside breaks releasing the hydrogen peroxide giving its glow. However, glowsticks emit light based on temperatures as well. The higher the temperature the brighter the glow.
TRIBOLUMINESCENCE:
Triboluminescence is when light is created through scratching, crushing or rubbing certain crystals, also known as friction.
Discovered by physicists Pierre and Jacques Curie in 1880.
When compressed positive and negative charges would appear on opposite faces. the crystal could drive current through a circuit and viseversa. when electricity runs through these crystals it allows them to change shape.
Piezoelectric materials have different structure however all have unitcells whick lack a center of symmetry. The stronger the compression on these materials the larger the voltage. When the crystal is stretched the charges switch which allows current flow the other way.
BIOLUMINESCENCE:
When light is fed off of living organisms as the resulted of a chemical
Light is produced with little to no heat and its reactions are replenishable compared to incandescent and Chemiluminescence.
EX. Fireflies are able to glow as they contain luciferin and luciferase. Glowing allows them to attract mates and lure prey. When they combine the presence of oxygen and ATP the reaction gives off energy in the form of visible light.
LIGHT-EMITTING DIODE (LED):
When light is created using electric current flowing in semi conductors.
Contain two specialized semi-conductors that are attached together and when a large voltage is applied they create visible light through a process known as electroluminescence.
They are more efficent as they produce less heat and can last very long. The light emitted from LEDs are very bright aswell. christmas lights, traffic lights etc.