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प्रश्न
Answer the following question.
Define coefficient of thermal conductivity.
उत्तर
The coefficient of thermal conductivity of a material is defined as the quantity of heat that flows in one second between the opposite faces of a cube of side 1 m, the faces being kept at a temperature difference of 1°C (or 1 K).
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Derive its expression for the coefficient of thermal conductivity.
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