How to calculate thermal vibration?

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    Thermal Vibration
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SUMMARY

This discussion centers on the feasibility of converting thermal vibrations into electrical energy using a capacitor heat engine composed of two charged parallel plates. Participants assert that while thermal vibrations occur due to temperature differences, extracting usable work from these vibrations violates the second law of thermodynamics. The conversation highlights the randomness of thermal vibrations and the necessity of a temperature gradient to generate coherent mechanical motion. Ultimately, the consensus is that without a temperature difference, the energy extracted from random vibrations is insufficient for practical work.

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  • Understanding of the second law of thermodynamics
  • Basic principles of thermal dynamics and heat engines
  • Knowledge of capacitor functionality and electrical energy conversion
  • Familiarity with statistical mechanics and random vibrations
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  • Explore the mechanics of heat engines and efficiency calculations
  • Study the relationship between temperature gradients and energy conversion
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Engineers, physicists, and researchers interested in thermodynamics, energy conversion technologies, and the principles governing heat engines will benefit from this discussion.

ctech4285
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lets say you build a capacitor heat engine that is made of two charged parallel plates. let's say one plate is hotter then the other and do to the thermal vibration one is moving more then the other. you should be able to convert the mechanical vibration to electrical current. now the question, what is the frequency and amplitude of an object vibrating do to the temperature?

also if there is no temp difference then there is still relative change in postion of the plates since they would vibrate somewhat radomly. then if you extract the electrical work you would violate some laws. so why can you not extract that work or is there no work done in the first place?
 
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Sorry, no, you can't turn heat directly into work. That's a violation of the second law of thermodynamics. To be more specific, the vibration is random: it isn't coherent enough to make it physically vibrate an entire object.
 
To be more specific, the vibration is random: it isn't coherent enough to make it physically vibrate an entire object.
thats not true
for +-intergers
random+random!=0

if you have an infinitily large statisical sample it tends to be might be 0 (not sure if that's true for all cases)
then again the vibration is not random it just apreas that way because if you have a large sample.
Sorry, no, you can't turn heat directly into work.
yeah hence you need a temp difference. i just don't really understand the mechanics of it in this particular case.

consider this, you take a very small charged mass hang it on a string in a vacum. let's say like 1000 atoms. and then you look and ajust a secondary field in such a way that the mass will vibrate less and less. in this case you would be extracting energy. if you need more energy to do it then you remove from mass in the ration of 1-(T1/T2) it would work but i don't see how.
anywho i just want to see if you could device a simple heat engine that can turn a temp difference into work
 

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