What Makes Electron Volts So Powerful in Relating Mass, Temperature, and Energy?

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    Electron Volt
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Discussion Overview

The discussion revolves around the concept of the electron volt (eV) and its relationship to mass, temperature, and energy. Participants explore how a unit of measure like the electron volt can represent such small energy and mass while also correlating to high temperatures, delving into definitions and interpretations of these relationships.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants assert that the electron volt can be defined in terms of mass, temperature, and energy, questioning how such small values can correspond to high temperatures.
  • Others argue that the electron volt is merely a unit of measure that is convenient in specific contexts, emphasizing that it is not a physical "thing."
  • It is noted that multiplying temperature by Boltzmann's constant yields energy, leading to potential confusion in interpreting temperature in electron volts.
  • Some participants clarify that when mass is expressed in electron volts, it refers to the energy equivalent of that mass, as described by the equation E = mc².
  • There is a discussion about the definition of "noun" and whether it should include abstractions like units of measure, with some participants challenging the notion that an electron volt represents a tangible entity.
  • A participant introduces the concept of electric charge, explaining that multiplying charge by voltage results in energy, which relates back to the definition of the electron volt.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the electron volt, with some emphasizing its role as a unit of measure while others discuss its implications in terms of mass and temperature. The discussion remains unresolved, with multiple competing interpretations present.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about the definitions of mass, temperature, and energy when expressed in electron volts. The relationship between these concepts is not fully resolved, and there are references to external sources for further clarification.

Kevin McHugh
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The electron volt can be defined as mass, temp and energy.

1 eV = 1.6022 x 10-19J

1 eV = 1.783 x 10-36kg

1 eV= 1.160 x 104K

How can something with such small energy and mass exhibit such high temperature? 104K is white hot
 
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Kevin McHugh said:
The electron volt can be defined as mass, temp and energy.
The electron volt can be used to define units of mass, temp, and energy.

Kevin McHugh said:
How can something with such small energy and mass exhibit such high temperature?
It's not a 'thing'; it's a unit of measure that proves convenient in the right context.
 
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It's unfortunately confusing because physicists are lazy. Electron volts are really a measure of energy. But if you multiply temperature by Boltzmann's constant you get an energy, so if we (lazily) say the temperature is 0.03 eV, what we really mean is that temperature times ##k_B## is 0.03 eV.
If we measure mass in electron volts, we really mean the energy equivalent of the mass is in electron volts. ##E = mc^2## gives the energy equivalent for a mass.
 
Doc Al said:
The electron volt can be used to define units of mass, temp, and energy.It's not a 'thing'; it's a unit of measure that proves convenient in the right context.

Electron volt is a noun, i.e. a person, place or thing. Besides being useful, how can an energy of 1.6022 x 10-19 J be equivalent to a temperature of 1.160 x1011 K?
 
I already answered that...
 
Khashishi said:
It's unfortunately confusing because physicists are lazy. Electron volts are really a measure of energy. But if you multiply temperature by Boltzmann's constant you get an energy, so if we (lazily) say the temperature is 0.03 eV, what we really mean is that temperature times ##k_B## is 0.03 eV.
If we measure mass in electron volts, we really mean the energy equivalent of the mass is in electron volts. ##E = mc^2## gives the energy equivalent for a mass.

Thanks man.
 
Khashishi said:
I already answered that...

I think I'll call you speedy :biggrin:
 
Kevin McHugh said:
Electron volt is a noun, i.e. a person, place or thing.
You need to expand your definition of noun to include abstractions, such as units of measure. The idea that there is some "thing" called an electron volt that has the given mass and temperature is incorrect.

Kevin McHugh said:
Besides being useful, how can an energy of 1.6022 x 10-19 J be equivalent to a temperature of 1.160 x1011 K?
How the eV can be used to measure temperature and mass, nicely summarized by Khashishi, is covered in the wiki page for electron volt.
 
In this context, electron actually means the amount of electric charge possessed by one electron or proton (a.k.a. an elementary charge), which is the same as 1.6 x 10-19 coulomb.

When you multiply charge by voltage, you get energy.
 

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