QAIPMT-2007-Ph-2353: NEET 2007 Physics - Class 12 AIPMT-2007-Ph-2353 Solution: Assuming the sun to have a spherical outer surface of radius r…

Assuming the sun to have a spherical outer surface of radius r radiating like a black body at temperature $t^\circ C$ the power received by a unit surface (normal to the incident rays) at a distance R from the centre of the sun is where $\sigma$ is the Stefan's constant. $\frac{4\pi r^2 \sigma (t+273)^4}{R^2}$ $\frac{16\pi^2 r^2 \sigma t^4}{R^2}$ $\frac{r^2 \sigma (t+273)^4}{R^2}$ $\frac{4\pi r^2 \sigma t^4}{R^2}$