The temperatures of two bodies $A$ and $B$ are respectively ${727^o}C$ and ${327^o}C$. The ratio ${H_A}:{H_B}$ of the rates of heat radiated by them is
AIIMS 2000, Medium
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(d) $Q \propto {T^4}$==>$\frac{{{H_A}}}{{{H_B}}} = {\left( {\frac{{273 + 727}}{{273 + 327}}} \right)^4} = {\left( {\frac{{10}}{6}} \right)^4} = {\left( {\frac{5}{3}} \right)^4} = \frac{{625}}{{81}}$
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