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Canada-0-LOGISTICS Azienda Directories
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Azienda News:
- Conductance and conductivity - Physics Stack Exchange
Conductance is the extrinsic property while conductivity is the intrinsic property This means that conductance is the property of an object dependent of its amount mass or physical shape and size, while conductivity is the inherent property of the material that makes up the object
- What is the difference between thermal conductivity and thermal . . .
2 In essense, thermal conductivity, $\kappa$, is how well the material passes on heat (thermal energy), while thermal diffusivity, $\alpha$, is how well the material passes on a temperature change
- The relation between permittivity and conductivity
The formula is $$\varepsilon=\varepsilon_r\varepsilon_0 + j\frac\sigma\omega,$$ but i know that $$\varepsilon=\varepsilon_r\varepsilon_0 $$ If this is equal then $\sigma$ should be zero according to this formula I think the above one is wrong Can anyone tell me how to calculate a material's conductivity from its permittivity?
- thermodynamics - What is the difference between heat transfer . . .
Which definition do you use as thermal conductivity? Does it differ from the heat transfer coefficient? It can indeed happen that the two coincide, depending on the definitions
- Why is conductivity defined as the inverse of resistivity?
Using conductance and conductivity can be useful when trying to calculate the total resistance of a material whose resistivity varies across its geometry See this question and this answer for an example
- electricity - In metals, the conductivity decreases with increasing . . .
In metals the conductivity decreases with increasing temperature However, in other classes of materials, known as semiconductors (e g germanium), conductivity increases with temperature over a wide range An increasing temperature means that, on average, there is greater mobility of the atoms that constitute the metal
- Charge conductivity by Non-Equilibrium Green Function Method
Conductance vs conductivity Let me first point out that for nanodevices we do not speak of conductivity, but of conductance Conductivity is a local property, which implies averaging over a physically small volume Such an averaging is impossible meaningless for nanodevices Importantly, some basic phenomena, like , could not be discussed with such averaging Landauer-Büttiker formalism The
- Conductance of semiconductors at very high temperatures
Semiconductors tend to have their restivity decrease as temperature increases as more electrons are promoted to conductance band But what happens to semiconductors at extremely high temperatures Does their conductivity continue to increase? Does there come a point where they lose all their conductivity Does the conductance band have an upper
- Are specific heat and thermal conductivity related?
17 For metals there is a connection between the thermal conductivity and electric conductivity (Wiedemann–Franz law) However specific heat is not directly related This is because electric and thermal conductivity are due to the electrons, however the specific heat is mostly due to the ion vibrations (phonons)
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