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Thermal resistance is a heat property and a measurement of a temperature difference by which an object or material resists a heat flow. Thermal resistance is the reciprocal of thermal conductance. *(Absolute) thermal resistance ''R'' in K/W is a property of a particular component. For example, a characteristic of a heat sink. *Specific thermal resistance or specific thermal resistivity ''R''λ in (K·m)/W is a material constant. *Thermal insulance has the units (m2K)/W in SI units or (ft2·°F·hr)/Btu in imperial units. It is the thermal resistance of unit area of a material. In terms of insulation, it is measured by the R-value. == Absolute thermal resistance == Absolute thermal resistance is the temperature difference across a structure when a unit of heat energy flows through it in unit time. It is the reciprocal of thermal conductance. The SI units of thermal resistance are kelvins per watt or the equivalent degrees Celsius per watt (the two are the same since the intervals are equal: Δ1 K = Δ1 °C). The thermal resistance of materials is of great interest to electronic engineers because most electrical components generate heat and need to be cooled. Electronic components malfunction or fail if they overheat, and some parts routinely need measures taken in the design stage to prevent this. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「thermal resistance」の詳細全文を読む スポンサード リンク
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