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Sometime around 1913 several copper samples from 14 important refiners and wire manufacturers were analyzed by the U.S. Bureau of Standards. The average resistance of the samples was determined to be 0.15292 Ω for copper wires with a mass of 1 gram of uniform cross section and 1 meter in length at 20 °C. In the United States this is usually ...
This means that all pure copper (Cu) wires (which have not been subjected to distortion of their crystalline structure etc.), irrespective of their shape and size, have the same resistivity, but a long, thin copper wire has a much larger resistance than a thick, short copper wire. Every material has its own characteristic resistivity.
Resistance thermometers, also called resistance temperature detectors (RTDs), are sensors used to measure temperature. Many RTD elements consist of a length of fine wire wrapped around a heat-resistant ceramic or glass core but other constructions are also used. The RTD wire is a pure material, typically platinum (Pt), nickel (Ni), or copper ...
Errata: The numbered references in the NSRDS-NBS-8 pdf are found near the end of the TPRC Data Book Volume 2 and not somewhere in Volume 3 like it says. [32] Aluminium oxide, porous 22% Porosity 2.3 [45] Constant 1000-1773 [45] This is number 54 on pages 73 and 76. Shakhtin, D.M. and Vishnevskii, I.I., 1957, interval 893-1773 Kelvins. [45 ...
Also called chordal or DC resistance This corresponds to the usual definition of resistance; the voltage divided by the current R s t a t i c = V I. {\displaystyle R_{\mathrm {static} }={V \over I}.} It is the slope of the line (chord) from the origin through the point on the curve. Static resistance determines the power dissipation in an electrical component. Points on the current–voltage ...
Temperature dependence of the mean free path has an exponential form /. The presence of the reciprocal lattice wave vector implies a net phonon backscattering and a resistance to phonon and thermal transport resulting finite λ L, [50] as it means that momentum is not conserved. Only momentum non-conserving processes can cause thermal resistance.
For wire sizes smaller than AWG No. 2 (33.6 mm 2, 0.0521 sq in), this term is also generally regarded as insignificant. R c , a {\textstyle R_{c,a}} is the effective thermal resistance between the conductor and the ambient conditions, which can require significant empirical or theoretical effort to estimate.
As quoted in an online version of: David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition.CRC Press. Boca Raton, Florida, 2003; Section 4, Properties of the Elements and Inorganic Compounds; Physical Properties of the Rare Earth Metals