Stefan Boltzmann Law

Assuming the sun to have a spherical outer surface of radius radiating like a black body at temperature the power received by a unit surface of the earth (normal to the incident rays) at a distance from the centre of the sun will be:
(where is Stefan's constant)

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A black body is at The rate at which it emits energy is proportional to:

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A black body at radiates heat at the rate of . At a temperature of , the rate of heat radiated in the same units will be:
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The total radiant energy per unit area, normal to the direction of incidence, received at a distance from the centre of a star of radius whose outer surface radiates as a black body at a temperature K is given by: (Where is Stefan’s constant):

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If the radius of a star is and it acts as a black body, what would be the temperature of the star at which the rate of energy production is

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