a) Find the total power radiated into space by the Sun, assuming it to be a perfect emitter at T = 5690 K. The Sun's radius is 7.0 108 m.(adsbygoogle = window.adsbygoogle || []).push({});

(b) From this, determine the power per unit area arriving at the Earth, 1.5 X 10^11 m away.

the formula for radiation is Power = (emittance factor)*(Stefan-Boltzmann constant)*(Area)*T^4. So I can find a) easily.

however for b, do I set up a ratio of some sort with the radius of the earth being (1.5 X 10 ^11 + radius of the earth) or just 1.5 X 10 ^11 ?

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# Homework Help: Determine the power per unit area arriving at the Earth

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