On what does the proportionality constant dep | vedclass

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(C) Newton's law of cooling states that the rate of loss of heat $dQ/dt$ is proportional to the temperature difference $(T - T_0)$ between the body an

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Both $(A)$ and $(B)$

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(C) Newton's law of cooling states that the rate of loss of heat $dQ/dt$ is proportional to the temperature difference $(T - T_0)$ between the body and its surroundings.Mathematically,$dQ/dt = k(T - T_0)$,where $k$ is the proportionality constant.The constant $k$ is given by $k = eA\sigma / ms$,where $e$ is the emissivity,$A$ is the surface area,$\sigma$ is the Stefan-Boltzmann constant,$m$ is the mass,and $s$ is the specific heat capacity.Since $k$ depends on the surface area $A$ and the nature of the surface (which determines emissivity $e$),the constant $k$ depends on both the nature and the area of the surface of the body.Therefore,the correct option is $C$.

On what does the proportionality constant depend in Newton's law of cooling?

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