If the initial temperatures of metallic sphere and disc, of the same mass, radius and nature are equal, then the ratio of their rate of cooling in same environment will be
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(d) $E \propto A{T^4}$
==> $\frac{{{E_{{\rm{sphere}}}}}}{{{E_{{\rm{Disc}}}}}} = \frac{{4\pi {r^2}}}{{2\pi {r^2}}} \times {\left( {\frac{T}{T}} \right)^4} = \frac{2}{1}$
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