A black body of surface area $10cm^2$ is heated to $127°C$ and is suspended in a room at temperature $27°C$ . The initial rate of loss of heat from the body at the room temperature will be ...... $W$
A$2.99 $
B$1.89 $
C$1.18 $
D$0.99 $
Medium
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D$0.99 $
d (d) Loss of heat $\Delta Q = A\varepsilon \sigma ({T^4} - T_0^4)t$
==> Rate of loss of heat $\frac{{\Delta Q}}{t} = A\varepsilon \sigma ({T^4} - T_0^4)$
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