How to calculate thermal vibration?

In summary, you can convert mechanical vibration into electrical current if there is a temperature difference between the two charged plates.
  • #1
ctech4285
32
0
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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  • #2
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.
 
  • #3
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
 

1. How do you calculate thermal vibration using the Debye model?

The Debye model is a method commonly used to calculate thermal vibration in solids. It involves calculating the average energy of the lattice vibrations using the phonon density of states and the Debye temperature. The formula for calculating thermal vibration using the Debye model is:
RMS atomic vibration amplitude = (3kBT/2π2υD3)1/2
where kB is the Boltzmann constant, T is the temperature in Kelvin, and υD is the Debye frequency.

2. What is the relationship between temperature and thermal vibration?

As the temperature of a material increases, the thermal energy also increases, causing the atoms in the material to vibrate more vigorously. This increase in thermal energy leads to an increase in the amplitude of atomic vibrations, resulting in a higher level of thermal vibration. Conversely, as the temperature decreases, the thermal energy decreases, resulting in a decrease in thermal vibration.

3. How does the mass of atoms affect thermal vibration?

The mass of atoms has a direct influence on thermal vibration. Lighter atoms have higher vibrational frequencies, meaning they can vibrate at a higher rate compared to heavier atoms. This results in a higher level of thermal vibration for materials with lighter atoms compared to those with heavier atoms.

4. Can thermal vibration be measured?

Yes, thermal vibration can be measured using various techniques such as X-ray diffraction, neutron scattering, and Raman spectroscopy. These techniques allow scientists to study the atomic vibrations in a material and calculate their amplitude and frequency, providing information about the level of thermal vibration.

5. How does thermal vibration affect the properties of a material?

Thermal vibration has a significant impact on the properties of materials. It affects factors such as thermal conductivity, specific heat capacity, and thermal expansion. For example, as the amplitude of thermal vibration increases, the thermal conductivity of a material decreases due to increased scattering of heat-carrying phonons. This phenomenon is known as phonon-phonon scattering and is a crucial factor in determining the thermal properties of materials.

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