Electricity & Resistance: The Physical Explanation

AI Thread Summary
The discussion centers on understanding the physical explanation behind the potential difference (U) in Ohm's law (U=RI). Participants reference the Drude model of charge transport as a foundational concept for explaining resistance in conductors. They also mention Onsager's contributions to solidifying Ohm's law, highlighting its connection to the Boltzmann equation and Kubo's theory of linear responses. The Drude model is noted as the simplest and most comprehensible approach to grasping these phenomena. Overall, the conversation emphasizes the theoretical frameworks that underpin the behavior of electricity and resistance in materials.
cosmonova
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Hello,

We all know Ohm's law U=RI, but I would like to know the physical explanation behind the apparition of the potential difference U of the resistance.

thank you.
 
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cosmonova said:
Hello,

We all know Ohm's law U=RI, but I would like to know the physical explanation behind the apparition of the potential difference U of the resistance.

thank you.

Look at the classical Drude model of charge transport in solids:

http://people.deas.harvard.edu/~jones/es154/lectures/lecture_2/drude_model/drude_model.html

Zz.
 
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IIRC, Ohm's law was given a firm footing by Onsager. If you can get Phys Rev, see here:

http://prola.aps.org/abstract/PR/v38/i12/p2265_1

Otherwise, just google Onsager and "Ohm's law" and eventually you'll find something.
 
krab said:
IIRC, Ohm's law was given a firm footing by Onsager. If you can get Phys Rev, see here:

http://prola.aps.org/abstract/PR/v38/i12/p2265_1

Otherwise, just google Onsager and "Ohm's law" and eventually you'll find something.

We all (should) know that Onsager's theory can be explained fully by mean of Boltzmann equation approach both to transport phenomena in solid state physics and plasma physics.Which should be coming from Kubo's theory of linear responses (both classical and quantum).Apparently there cannot be a deeper explanation of Georg Ohm'1828 law.
But i' have to stick with Zz's referring to the Drude model as being the most simple & comprehendable approach to what's really happenig in a conductor.

Daniel.

PS.What i said applies to another linear effect in conducting media,the classical Hall effect.
 
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