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Explain how the gravitational force between the sun and earth changes as the earth moves from position A to B.

We all know that the sun revolves around the sun in the elliptical orbit which is oval in shape.
We also know that the gravitational force between different heavenly bodies is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers. In position 'A', the distance is shorter; so the gravitational force is higher but in position 'B', the distance is longer; so the gravitational force is less than that in position 'A'.