A black body is heated from ${27^o}C$ to ${127^o}C$. The ratio of their energies of radiations emitted will be
AIIMS 2001, Medium
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(d) $\frac{{{Q_1}}}{{{Q_2}}} = \frac{{T_1^4}}{{T_2^4}} = {\left( {\frac{{273 + 27}}{{273 + 127}}} \right)^4} = {\left( {\frac{{300}}{{400}}} \right)^4} = \frac{{81}}{{256}}$
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