An object is at a temperature of ${400^o}C$. At what temperature would it radiate energy twice as fast? The temperature of the surroundings may be assumed to be negligible
Medium
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(d) $\frac{{{E_2}}}{{{E_1}}} = {\left( {\frac{{{T_2}}}{{{T_1}}}} \right)^4}$==> $\frac{2}{1} = {\left( {\frac{{420 + 273}}{T}} \right)^4}$$ = {\left( {\frac{{673}}{T}} \right)^4}$
==> $T = {2^{1/4}} \times 673$ $= 800K.$
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