At temperature $T$ , the power radiated by a body is $Q$ watts. At the temperature $3T$ the power radiated by it will be
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(d) Power radiated $P \propto {T^4}$
==> $\frac{{{P_1}}}{{{P_2}}} = {\left( {\frac{{{T_1}}}{{{T_2}}}} \right)^4}$
==> $\frac{Q}{{{P_2}}} = {\left( {\frac{T}{{3T}}} \right)^4}$ ==> ${P_2} = 81Q$
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