The spectrum of a black body at two temperatures $27^oC$ and $327^oC$ is shown in the figure. Let $A_1$ and $A_2$ be the areas under the two curves respectively. The value of $\frac{{{A_2}}}{{{A_1}}}$ is
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(d) Area under given curve represents emissive power and emissive power $\propto T_4 \Rightarrow \,\,A \propto {T^4}$
$ \Rightarrow \,\frac{{{A_2}}}{{{A_1}}} = \frac{{T_2^4}}{{T_1^4}} = \frac{{{{(273 + 327)}^4}}}{{{{(273 + 27)}^4}}} = {\left( {\frac{{600}}{{300}}} \right)^4}$= $\frac{{16}}{1}$
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