Assuming sun to be a spherical body of radius R at a temperature of T K , solve total radiant power,

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10-2.Transmission of Heat

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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

${R^2}\sigma {T^4}/{r^2}$

Solution

$\frac{{s\left( {{A_{sun}}} \right){T^4}}}{{4\pi {r^2}}} \times \pi r_0^2$

Standard 11

Physics

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