What causes light to become brighter?

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Discussion Overview

The discussion centers on the mechanisms behind the brightness of light, particularly in relation to light bulbs and the effects of voltage and current. It explores concepts from both classical and quantum physics, including photon energy, wave-particle duality, and the relationship between temperature and light emission.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that increasing the voltage in a light bulb leads to increased current, which in turn results in more photons being emitted, thus making the light brighter.
  • Others clarify that brightness is a measure of the number of photons emitted, and that each photon has energy determined by its frequency or wavelength.
  • One participant questions the relationship between photon energy and brightness, noting that while more photons contribute to brightness, the energy of individual photons varies with frequency.
  • There is a discussion about whether photons have size, with some asserting that photons do not have a volume and are better described as waves of electric and magnetic fields.
  • Questions arise regarding the nature of light travel, with some participants suggesting that photons follow the shape of waves, while others emphasize the wave-particle duality of light.

Areas of Agreement / Disagreement

Participants generally agree on the relationship between voltage, current, and brightness in light bulbs, but there are competing views regarding the nature of photons, their energy, and the mechanics of light travel. The discussion remains unresolved on several points, particularly regarding the implications of quantum mechanics on the understanding of light.

Contextual Notes

Some claims depend on specific definitions of brightness and energy, and there are unresolved questions about the relationship between wave behavior and particle characteristics of light.

MegaDeth
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Why and how does light get brighter as you increase a light bulbs voltage?
 
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for a given frequency, brightness is just a measure of the number of photons. When you increase the current in a bulb wire it gets hotter and emits more photon. When you increase the voltage, you increase the current.

SO ... more voltage => more current => more photons => brighter
 
Ahh right. So when current passes through and light bulb and heats it up, is the light produced when the electrons in the filament gain energy so they go up a shell then since there's an empty space, it goes back down into that space. So then it's releases that energy as a photon? So, by taking into account what you said, basically, as the temperature increases, from more current, the filament gets hotter, so more electrons are moving?
 
That is pretty much correct. The more current through the filament the more it heats up. The more it heats up the more light it produces.
 
Great! Only things is, I am watching this program about Quantum Mechanics and the guy on it said that photons of different frequencies of light have different amounts of energies. He was talking about the photoelectric effect. Is this true? Because I though than every photon has the same amount of energy, but the energy only increases because its frequency increases. So more photons pass a certain point in a period of time. So there is more energy but the amount of energy in each photon is the same.
 
Each photon has a specific amount of energy that is determined by its wavelength or frequency. Red light has less energy than blue light because its wavelength is longer. Higher energy light isn't brighter though. Brightness is purely due to the amount of photons entering your eye.
 
Oh, so every photon of a certain frequency has the same amount of energy but the energy of photons of different wavelengths or frequency. Are photons all the same size?
 
I don't believe photons have a volume associated with them. IE they don't have a size. They are a wave of electric and magnetic fields that propegates through space.
 
How does light actually travel? I know it travels in waves, do the photons follow that the shape of the wave? Also, why do they travel like that? Why not it a straight, direct line?
 
  • #10
The waves ARE the photon. The electric and magnetic field oscillate back and forth perpendicular to each other.
The depictions of all particles of little balls is incorrect. To understand the reality you would need to read up on Quantum Mechanics.
 

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