Assuming the sun to be a spherical body of radius $R$ at a temperature of $T$ $K$, evaluate the total radiant power, incident on earth, at a distance $r$ from the sun- (when radius of earth is $r_0$)
Assuming the sun to be a spherical body of radius $R$ at a temperature of $T$ $K$, evaluate the total radiant power, incident on earth, at a distance $r$ from the sun- (when radius of earth is $r_0$)
- A
$4\pi r_0^2{R^2}\sigma {T^4}/{r^2}$
- B
$\pi r_0^2{R^2}\sigma {T^4}/{r^2}$
- C
$r_0^2{R^2}\sigma {T^4}/4\pi {R^2}$
- D
${R^2}\sigma {T^4}/{r^2}$
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