Question

what causes slight flattening of the earth at two poles?

Answer 1

We know that the Earth spins around itself at tremendous speed. This spinning results in an outward centrifugal force which is highest at the equator and gradually decreases to zero at the pole.

This results in slightly greater gravitational pull at the poles than at the equator. This causes the equator to bulge outward and the poles to flatten slightly.

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