Two identical metal balls at temperature ${200^o}C$and ${400^o}C$ kept in air at ${27^o}C$. The ratio of net heat loss by these bodies is
Medium
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(d) If temperature of surrounding is considered then
net loss of energy of a body by radiation $Q = A\varepsilon \sigma ({T^4} - T_0^4)t$
net loss of energy of a body by radiation $Q = A\varepsilon \sigma ({T^4} - T_0^4)t$
==>$Q \propto ({T^4} - T_0^4)$
==> $\frac{{{Q_1}}}{{{Q_2}}} = \frac{{T_1^4 - T_0^4}}{{T_2^4 - T_0^4}}$
$ = \frac{{{{(273 + 200)}^4} - {{(273 + 27)}^4}}}{{{{(273 + 400)}^4} - {{(273 + 27)}^4}}}$$ = \frac{{{{(473)}^4} - {{(300)}^4}}}{{{{(673)}^4} - {{(300)}^4}}}$
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