Temperature of a black body increases from ${327^o}C\,{\rm{to}}\,{\rm{92}}{{\rm{7}}^{\rm{o}}}C$, the initial energy possessed is $ 2KJ$ , what is its final energy ..... $KJ$
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(a) $\frac{{{Q_2}}}{{{Q_1}}} = {\left( {\frac{{{T_2}}}{{{T_1}}}} \right)^4} = {\left( {\frac{{273 + 927}}{{273 + 327}}} \right)^4} = {\left( {\frac{{1200}}{{600}}} \right)^4} = 16$
==> $Q2$ $ = 32\;KJ$
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