Problem about application of E = hv to white light

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SUMMARY

The discussion centers on the application of the equation E = hv to the phenomenon of white light. Participants clarify that white light is perceived due to the presence of multiple photon energies, which stimulate various receptors in the human eye. A 100-watt light bulb emits 100 Joules of energy per second across a spectrum of frequencies, not just a single frequency. The equation E = hv applies to individual photons, not to the collective emission of light that results in the perception of white light.

PREREQUISITES
  • Understanding of the equation E = hv in quantum mechanics
  • Knowledge of photon energy and frequency relationships
  • Familiarity with the visible light spectrum
  • Basic principles of human vision and light perception
NEXT STEPS
  • Research the concept of photon energy and its implications in quantum mechanics
  • Explore the visible light spectrum and its interaction with human receptors
  • Study the principles of light emission from various sources, such as incandescent bulbs
  • Learn about the limitations of applying E = hv to collective light emissions
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Students of physics, educators explaining light phenomena, and anyone interested in the principles of light and vision.

Zynoakib
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The reason why we see white light is because we see all the light in the visible lights spectrum.

So let's say I have a light bulb that gives out white light, the reason why it gives out light its because it keeps emitting a constant amount of energy. By E = hv, we should only be able to see one kind of light. ( for instance, the energy emitted by light is 100 J and the frequency of the light wave should be 100/h, which means one kind of light) So why can we still see white light?

What is wrong with my concept? Thanks a lot!
 
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Zynoakib said:
By E = hv, we should only be able to see one kind of light. ( for instance, the energy emitted by light is 100 J and the frequency of the light wave should be 100/h, which means one kind of light) So why can we still see white light?

You logic for that conclusion escapes me.

The reason we see white light is we have receptors for many different photon energies and when they are all present we perceive that as white.

Thanks
Bill
 
A 100 watt light bulb radiates 100 Joules per second in a wide range of frequencies, only some of which are in the visible part of the spectrum. So in 1 second 100 Joules of photons are emitted in many colors. E=hv gives the energy of just *one* photon, and v=E/h its color. Since, there is no such thing as a white photon you cannot use use v = E/h this way. Using the formula for v with E = 100 Joules would only make sense, for example, if the 100 watt bulb radiated just one 100 Joule photon per second. And that would not be white light!
 
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James_Harford said:
Using the formula for v with E = 100 Joules would only make sense, for example, if the 100 watt bulb radiated just one 100 Joule photon per second. And that would not be white light!

This made me laugh :-P I mean, it's true of course, but my God is it an understatement.
 
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