Question

Why is it assumed that gravitational field exists all around the earth

Answer 1

Explanation:

We have observed a gravitational field existing all around the Earth, by observing the motion of the hundreds of satellites that orbit the earth. None of them show any anomalies that would result from an absence of gravitation. [Some orbits show slight variations from the theoretical ellipsoid, caused by variations in the density of the land below, but that’s not absence of gravity].

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