The intensity of solar radiation incident normally on the upper atmosphere of Earth…
PHYSICS · Multi-part · CBSE · Physics · Thermal Properties of Matter · Thermal Properties of Matter
Problem
The intensity of solar radiation incident normally on the upper atmosphere of Earth (the solar constant) is approximately 1.4kW m−2. The mean distance between the centres of Earth and Sun is 1.5×1011m and the radius of the Sun is 7.0×108m. Treat the Sun as a perfect black sphere.
(i) Show that the total power emitted by the Sun can be expressed in terms of the solar constant and the mean Earth–Sun distance.
(ii) Derive an expression for the surface temperature of the Sun in terms of the total power obtained in part (i), the radius of the Sun and relevant physical constants.
(iii) Calculate the surface temperature of the Sun using the given data.