why earth revolves around the sun??

Earth revolves round the sun because of the mutual force of attraction between these two bodies. This force is known as the gravitational force. This is proportional to the product of the masses of the two bodies and inverse of the square of distance between the two bodies.
Geophysical interpretations from gravity surveys are based on the mutual attraction experienced between two masses as first expressed by Isaac Newton in his classic work Philosophiae naturalis principia mathematica (The mathematical principles of natural philosophy). Newton's law of gravitation states that the mutual attractive force between two point masses, m1 and m2, is proportional to one over the square of the distance between them. The constant of proportionality is usually specified as G, the gravitational constant. Thus, we usually see the law of gravitation written as
F = G m1 m2 / r^2
where F is the force of attraction, G is the gravitational constant, and r is the distance between the two masses, m1 and m2. 'G' is in fact the universal gravitational constant, distinctly different from 'g' which is the earth’s gravitational acceleration.

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Apoorva Arora

IIT Roorkee

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