How incandescent light bulbs create light

  • Thread starter Yaus Man
  • Start date
  • Tags
    Light
In summary, the light produced by a tungsten incandescent light bulb can be attributed to both the current passing through with a high voltage, causing electrons to jump to a higher energy level and drop back down, and the high temperature of the tungsten causing it to radiate visible light. However, incandescence is the primary source of light in a light bulb due to the collective behavior of atoms in a solid medium.
  • #1
Yaus Man
2
0
I'm looking at how incandescent light bulbs create light in a more in depth manner, not just "filament gets hot and it glows". I want to know the actual science in an atomic level.

I have been researching through books and the internet, and have yet to come to a conclusion whether the light from a tungsten incandescent light bulb comes from:

a) The current passing through with a high voltage gives energy to electrons to jump to a higher energy level, and drops back down to ground state, spontaneously emitting photons (visible light).

or

b) Incandescence, simply due to the high temperature, which meant that the tungsten radiates some visible light instead of only infrared.

or

c) Both?

I am really confused by all these information, some saying it's (a), some say it's (b).
 
Science news on Phys.org
  • #2
Yaus Man said:
b) Incandescence, simply due to the high temperature,
A continuous spectrum;
Yaus Man said:
higher energy level, and drops back down to ground state
A line spectrum; which makes sense?
 
  • #3
Bystander said:
A continuous spectrum;

A line spectrum; which makes sense?

So are you saying it's both? Both are responsible for producing light?

Thanks a lot I really appreciate your reply.
 
  • #4
Do you see any hint of a line spectrum from an incandescent lamp? Compare it to a CFL --- look at them alongside one another through beveled glass.
 
  • #5
Yaus Man said:
So are you saying it's both?
No. He's asking you what you think the spectrum of light looks like.

Consider this quote from the FAQ https://www.physicsforums.com/threads/do-photons-move-slower-in-a-solid-medium.511177/
ZapperZ said:
Do Photons Move Slower in a Solid Medium?
When atoms and molecules form a solid, they start to lose most of their individual identity and form a "collective behavior" with other atoms. It is as the result of this collective behavior that one obtains a metal, insulator, semiconductor, etc. Almost all of the properties of solids that we are familiar with are the results of the collective properties of the solid as a whole, not the properties of the individual atoms.
 
Last edited by a moderator:
  • #6
Yaus Man said:
So are you saying it's both? Both are responsible for producing light?

Both would be responsible to some degree, but incandescence is overwhelmingly dominant in a light bulb.
 

1. How does an incandescent light bulb create light?

An incandescent light bulb creates light through a process called incandescence. This occurs when an electric current passes through a thin filament, typically made of tungsten, inside the bulb. The filament heats up and produces light as a result of its high temperature.

2. What materials are used to make the filament in an incandescent light bulb?

The most common material used to make the filament in an incandescent light bulb is tungsten. Tungsten has a high melting point and is able to withstand the high temperatures needed for incandescence. Other materials, such as carbon or a tungsten alloy, may also be used.

3. Why do incandescent light bulbs eventually burn out?

Incandescent light bulbs eventually burn out because the high temperatures needed to produce light cause the filament to slowly evaporate. This results in the filament becoming thinner and eventually breaking, causing the bulb to stop working.

4. How efficient are incandescent light bulbs?

Incandescent light bulbs are not very efficient, as only about 10% of the energy they use is converted into light. The rest of the energy is emitted as heat, making them inefficient for lighting purposes. This is one of the reasons why many countries have banned the use of incandescent light bulbs in favor of more energy-efficient options.

5. Can incandescent light bulbs be recycled?

Yes, incandescent light bulbs can be recycled. However, they cannot be recycled in the same way as other types of light bulbs, such as LED or CFL bulbs. Incandescent bulbs should be taken to a recycling center that specifically handles them, as they contain small amounts of mercury that need to be properly disposed of.

Similar threads

  • Optics
Replies
2
Views
1K
  • Electrical Engineering
Replies
3
Views
1K
  • Classical Physics
Replies
16
Views
3K
  • Engineering and Comp Sci Homework Help
Replies
5
Views
1K
Replies
2
Views
2K
Replies
1
Views
1K
  • Thermodynamics
Replies
1
Views
890
  • Electrical Engineering
Replies
15
Views
4K
  • Introductory Physics Homework Help
Replies
15
Views
1K
Back
Top