Questions tagged [resistivity]

A direct measure of how resistive a material is with higher numerical values meaning that the material is more resistive. It is the inverse of conductivity. The units of resistivity are $ \Omega* m $ or $ \Omega* cm $ (in the semiconductor industry) - not to be confused with resistance that is similar but does not have units of length associated with it.

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What's a conceptual way to understand ohm-cm?

Resistivity is defined in units of \$\Omega \times \textrm{cm}\$. I don't conceptually understand what is meant by the unit. If it was \$\Omega / \textrm{cm}\$, that would be easy to understand - a certain number of ohms for every centimeter. How…
elile
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Can the resistance between two points in air be calculated? How?

If I have just a battery, the terminals are separated by air, a very good insulator. We can say, practically, that no current flows. However, air has a very large, but finite resistivity. Wikipedia gives a range of \$1.3\cdot 10^{16}\$ to \$3.3\cdot…
Phil Frost
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How to convert between different units of resistivity

Some data sheets specify units of resistivity as Ω/sq/mil. How could I convert that to units of Ω-cm?
user510
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Resistivity: related to V/I or dV/dI?

The resistivity of Tungsten is given by \$\rho(T) \propto T^{1.209}\$ (from Paul Gluck's Physics Project Lab). Let's assume that we can ignore the changes in the geometry of the wire due to temperature change. Does that mean that for a Tungsten…
Rd Basha
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Resistivity of Ferromagnetic Substance

How does the resistivity of a ferromagnetic material change as the material is being magnetized (magnetic domains aligned)?
A. Furtek
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Resistance between two points in/on a large volume/sheet?

I want to model the resistance between two points on a large mass of uniform resistivity. There are two cases I am particularly interested in: a) a cuboid (e.g. a tank of conductive fluid), we could say it is axis-oriented with (0,0,0) and (w,h,d)…
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Question on Electricity (A-level)

A cell connected to two resistors P and Q that are connected in parallel. The resistors are metal wires made of the same material. The length of P is L and the length of Q is 2L. The diameter of P is d/2 and the diameter of Q is d. The current…
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Resistance and Resistivity

How do I calculate the radius of a copper wire dissipating heat of 100mW given that the volume of the conductor is 20mm^3 and is carrying a current of 40nA. Resistivity of copper is 0.0000172.