If the radius of a star is $R$ and it acts as a black body, what would be the temperature of the star, in which the rate of energy production is $Q$?
($\sigma$ stands for Stefan's constant)
AIPMT 2012, Medium
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$According\,to\,Stefan's\,law,\,Q=\sigma\,AT^4$
or $T = {\left( {\frac{Q}{{\sigma A}}} \right)^{1/4}} = {\left( {\frac{Q}{{\sigma 4\pi {R^2}}}} \right)^{1/4}}$
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