(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The Sun emits electromagnetic waves (including light) equally in all directions. The intensity of the waves at the Earth's upper atmosphere is 1.5 kW/m2. At what rate does the Sun emit electromagnetic waves? (In other words, what is the power output?)

The answer is supposed to be in Watts, not kW.

2. Relevant equations

Surface area of sphere X Intensity = Power

3. The attempt at a solution

The surface area for a sphere = 4[tex]\pi[/tex]r^{2}. The radius of the sun in meters is 695,500,000 m.

The given intensity is 1.5 kW, which I converted to 1500 W.

4[tex]\pi[/tex](695500000)^{2}(1500) = Power output

9.1e21 = Power output

But this answer is coming up as incorrect. I'm not sure how to go about this.

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# Homework Help: Power Output and Intensity

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