Infrared radiation from friction

AI Thread Summary
Frictional forces generate infrared radiation primarily through the conversion of mechanical energy into thermal energy, which excites electrons and causes them to emit photons as they return to lower energy states. The discussion highlights that heat, resulting from friction, leads to different forms of infrared radiation based on temperature levels, including thermal IR and near IR. Sparks produced during friction involve material being heated to high temperatures, further illustrating the energy transformation at play. A deeper understanding of molecular behavior and black body radiation is essential for grasping these concepts accurately. The complexity of these interactions suggests that modeling them may require considering light as a wave rather than solely as particles.
Strange design
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Hello all,
I was driving down the road yesterday, and I realized that I don't really have a solid grasp on how frictional forces cause infrared radiation. Can anyone explain, or direct me to a resource that explains, how this happens at the atomic level?

I am thinking that the work done forcing the two surfaces together, against the EM forces, gives energy to the individual electrons, which move to a higher state, and then they release photons as they transition back to a lower state, but this is the oversimplified model I have in my head and is probably wrong.

Any help is appreciated.
 
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Friction causes heat.
Heat causes IR. Low heat, thermal IR. More heat near IR. More still, visible glowing.

Also, when friction causes sparks to fly - those sparks are material torn from the surface and raised to high temperatures.
 
Strange design said:
I am thinking that the work done forcing the two surfaces together, against the EM forces, gives energy to the individual electrons, which move to a higher state, and then they release photons as they transition back to a lower state, but this is the oversimplified model I have in my head and is probably wrong.

@.Scott gave you the answer. Heat is more than electrons changing energy states. You need to study how molecules and crystal lattices change behavior with temperature. The next step is how do solid bodies radiate as a function of temperature.

If you want to think it through one particle at a time, you'll have enough to keep your mind occupied for many many miles of driving. :rolleyes:
 
Ok, so should I rather consider the surface as a mass of oscillators already releasing IR, and then the friction increases the amplitude of the oscillations?
 
I would start with black body radiation. That is what is at the root. The article offers several models for what is happening.

https://en.wikipedia.org/wiki/Black-body_radiation

It can get very complex.

Human-Infrared.jpg
 
Thanks Anorlunda. I think where I am going wrong is that I am attempting to develop a conceptual model for these friction interactions where I am regarding light as a particle, but these interactions may only be able to be modeled with light regarded as a wave.
 
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