Three identical metal spheres (of same surfac | vedclass

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(A) According to Stefan-Boltzmann Law,the rate of heat loss by radiation is given by $dQ/dt = e \sigma A (T^4 - T_0^4)$,where $e$ is the emissivity of

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black,red,white

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(A) According to Stefan-Boltzmann Law,the rate of heat loss by radiation is given by $dQ/dt = e \sigma A (T^4 - T_0^4)$,where $e$ is the emissivity of the surface.For a given temperature and surface area,the rate of cooling is directly proportional to the emissivity $(e)$ of the surface.Black surfaces have the highest emissivity (close to $1$),followed by dark colors like red,while white or polished surfaces have the lowest emissivity.Therefore,the order of cooling rate from maximum to minimum is: black > red > white.

Three identical metal spheres (of same surface area) have red,black,and white colors and they are heated up to the same temperature. They are allowed to cool. Arrange them from maximum rate of cooling to minimum rate of cooling.

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