A black body of surface area $10cm^{2}$ is heated to $127℃$ and is suspended in a room at temperature $27℃$. The initial rate of loss of heat from the body at the room temperature will be

Question

Dr. Abubacker · Accepted Answer

(d) Loss of heat $\mathrm{\Delta}Q = A\varepsilon\sigma\left( T^{4} - T_{0}^{4} ight)t$
$\Rightarrow$ Rate of loss of heat $\frac{\mathrm{\Delta}Q}{t} = A\varepsilon\sigma(T^{4} - T_{0}^{4})$
$= 10 	imes 10^{- 4} 	imes 1 	imes 5.67 	imes 10^{- 8}\{(273 + 127)^{4} - (273 + 27)^{4}\}$
$= 0.99\ W$

Q. A black body of surface area $10cm^{2}$ is heated to $127℃$ and is suspended in a room at temperature $27℃$. The initial rate of loss of heat from the body at the room temperature will be

Explanation

Reviewed by Dr. Abubacker

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