What fraction of the Sun's Energy does the Earth Recieve?
Surface area of circle =πr2
Radius of Earth = 3,963.19 miles
Area of shadow cast by earth: π(3,963.19)2= 49,344,603 sq. miles
Surface area of sphere = 4πr2
Distance from Earth to Sun: 92,935,700 miles
Surface area of sphere with radius 92,935,700 miles: 108,536,300,119,852,515 sq. miles
Divide one by the other and the answer is 0. 000 000 000 454 637
That's 454 trillionths of the sun's energy. Roughly half a billionth.
Percentage-wise, the Earth gets 0.0000000454637% or 45 billionths of one percent of the sun's energy.