It may be surprising, but The Earth carries a negative electric charge of roughly 500 x 103 Coulombs. This charge is maintained by thunderstorms, which deposit negative charge on the earth (worldwide) at the rate of about 10³ amperes. If you consider the earth as a sphere, and use the fact that the potential of a charged sphere is the same as that of a point charge at the centre, find the magnitude of the electric potential at the surface of the earth. The radius of the Earth is 6370 km. What is the electric field due to this charge?

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