thermal conductivity

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thermal conductivity (K) A parameter used as a measure of how well a material conducts heat (for example, for copper K = 385 W/m/K, for air K = 0.02 W/m/K). K forms the constant of proportionality in the heat-conduction-rate equation: dQ/dt = −KAdθ/dl, where dQ/dt is the heat conduction rate (in joules per second), A is the cross-sectional area of a uniform sample (in square metres), and dθ/dl is the temperature gradient along the sample (in kelvin per metre). Compare THERMAL RESISTIVITY.