Electricity & Resistance: The Physical Explanation

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    Electrical Resistance
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Discussion Overview

The discussion centers around the physical explanation for the potential difference (voltage) across a resistor as described by Ohm's law (U=RI). Participants explore various theoretical models and historical perspectives related to this phenomenon.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant seeks to understand the physical basis for the potential difference in resistors as described by Ohm's law.
  • Another participant references the classical Drude model of charge transport in solids as a relevant framework for understanding this phenomenon.
  • A different participant mentions Onsager's contributions to the theoretical foundation of Ohm's law, suggesting that it can be further explored through the Boltzmann equation and Kubo's theory of linear responses.
  • There is a suggestion that the Drude model remains a simple and comprehensible approach to explaining what occurs in a conductor.
  • A participant notes that the discussion of Ohm's law also relates to other linear effects in conducting media, such as the classical Hall effect.

Areas of Agreement / Disagreement

Participants express different perspectives on the best models to explain the potential difference in resistors, with no consensus on a single explanation. Some favor the Drude model for its simplicity, while others highlight the contributions of Onsager and the Boltzmann equation.

Contextual Notes

The discussion includes references to various theoretical models and historical contributions, but participants do not resolve the complexities or limitations of these models in explaining Ohm's law.

Who May Find This Useful

This discussion may be of interest to those studying electrical engineering, solid-state physics, or anyone looking to deepen their understanding of the theoretical underpinnings of electrical resistance and Ohm's law.

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.
 
Last edited by a moderator:
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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