Question

why thermal conductivity decreases when the temperature difference increases

Answer #1

Ans :

The thermal conductivity of substances is dependent on various factors such as : chemical composition , phase change , temperature etc.

When the temperature of a metal is increased , the mean free path of the molecules decreases. The thermal conductivity directly relates with the mean free path and absolute temperature.

This causes a decrease in the conduction of heat , so the the thermal conductivity decreases when the temperature difference increases.

Why does the conductivity of a semiconductor increase with
increased temperature, but a metal’s conductivity decreases?

Why viscosity of gasses increases with temperature where as
viscosity of liquid decreases with temperature?
Please
Explain

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A.
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A scientist designs an experiment to determine the thermal
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If the heat transfer through the bar was measured to be 500 W,
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