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## Homework Statement

The Earth's radius is 6370 km . There is a downward-pointing electric field in the atmosphere above the Earth's surface, of average magnitude 140. N/C .

a) What is the flux of the electric field out of the Earth?

b) What is the charge on the Earth?

## Homework Equations

[itex]\Phi[/itex]=[itex]\vec{E}[/itex][itex]\bullet[/itex]A

## The Attempt at a Solution

I figured that this would be a simple problem of the electric flux through a sphere, so I thought if I used the above equation and by plugging in the area of the sphere I would get the right answer for a), but the computer is saying I'm incorrect. :( I got an answer of 7.13x10^16 N*m^2/C. I know that flux involves integration, but I'm only just starting to learn it so I don't know how to use integration in a problem like this yet. Any help would be really appreciated! Thanks