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This is a collection of temperature conversion formulas and comparisons among eight different temperature scales, several of which have long been obsolete.. Temperatures on scales that either do not share a numeric zero or are nonlinearly related cannot correctly be mathematically equated (related using the symbol =), and thus temperatures on different scales are more correctly described as ...
is the temperature (in kelvins), R {\displaystyle R} is the resistance at T {\displaystyle T} (in ohms), A {\displaystyle A} , B {\displaystyle B} , and C {\displaystyle C} are the Steinhart–Hart coefficients , which are characteristics specific to the bulk semiconductor material over a given temperature range of interest.
The effective temperature coefficient varies with temperature and purity level of the material. The 20 °C value is only an approximation when used at other temperatures. For example, the coefficient becomes lower at higher temperatures for copper, and the value 0.00427 is commonly specified at 0 °C. [53]
is the temperature gradient (K·m −1) across the sample, A {\displaystyle A} is the cross-sectional area (m 2 ) perpendicular to the path of heat flow through the sample, Δ T {\displaystyle \Delta T} is the temperature difference ( K ) across the sample,
Consider a solid material placed between two environments of different temperatures. Let be the temperature at = and be the temperature at =, and suppose >. An example of this scenario is a building on a cold winter day; the solid material in this case is the building wall, separating the cold outdoor environment from the warm indoor environment.
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 ...
Ohm explained his experimental results by a slightly more complex equation than the modern form above (see § History below). In physics, the term Ohm's law is also used to refer to various generalizations of the law; for example the vector form of the law used in electromagnetics and material science:
A cesium atom with a velocity of 7 mm/s is equivalent to a temperature of about 700 nK (which was a record cold temperature achieved by the NIST in 1994). Estimates of the differences between thermodynamic temperature and the ITS-90 (T − T 90) were published in 2010. It had become apparent that ITS-90 deviated considerably from PLTS-2000 in ...