Hi everyone. Firstly, I know that intensity= Power/Area. But this question made me my mind confused.(adsbygoogle = window.adsbygoogle || []).push({});

The question shows the sun shining upon the Earth and the soln is:

Only the hemisphere facing the Sun receives energy at any moment.

power received by Earth

= intensity × area of Earth facing the Sun

And it shows the area of the Earth facing the sun is projected to a circle (pi R square, where R is the radius of the circle)!!!!!!! But shouldnt the area be the half the area of a Earth (sphere)????

Anyone can help me? Im really confused. Thanks.

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# Question about intensity and area

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