Understanding the Science Behind Light Bulbs

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Light bulbs operate by passing electrical current through a filament, typically made of tungsten, which heats up and emits light. The process involves thermal radiation rather than electron transitions, as the energy levels involved in incandescent bulbs are too high for typical electron excitation. The filament also undergoes a self-healing process where tungsten atoms that evaporate from hotter areas migrate to cooler parts, maintaining its integrity. While the initial question touches on electron behavior, the primary mechanism of light production in incandescent bulbs is thermal rather than electronic. Understanding these processes clarifies the science behind how light bulbs function.
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How does the light bulb work exactly? Does the current that does through the tungstern, or whatever material is used, collide with the elections in the resistor and push then up to a higher energy state? And when the electrons naturally fall back down to their ground state, the energy is released in the from of photons?
 
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In an incandescent bulb, the electrical current heats the filament. The thermal light given off is due to a variety of processes, but electron transistion are not generally one of them- the energies are much higher than those present in vibrational and rotational transitions. there's also a lot of chemistry involved, including the fact that the filament 'self heals' as W atoms are boiled off from some locations and migrate to hotter (thinner) parts of the filament.
 
Ghost803 said:
How does the light bulb work exactly? Does the current that does through the tungstern, or whatever material is used, collide with the elections in the resistor and push then up to a higher energy state? And when the electrons naturally fall back down to their ground state, the energy is released in the from of photons?

Please note that there have been several threads here that have dealt with the same question. Read this, for example:

https://www.physicsforums.com/showthread.php?t=304369

Zz.
 
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