Q2 of 38 Page 57

As observed from earth, the sun appears to move in an approximate circular orbit. For the motion of another planet like mercury as observed from earth, this would

All the planets move around the sun in approximate circular orbits dur to gravitational force of attraction between the sun and the planet.



Where,


M1 and M2 are masses of two bodies and r is the distance between them


This gravitational force is inversely proportional to the square of distance between them and hence the planet revolves in circular orbits.


Similarly, Mercury experiences force of gravitational attraction both from the Sun and the Earth. But since the mass of sun is massive, the force due to sun is very large compared to force due to earth.


Therefore, mercury revolves in circular orbit around sun and not around earth.

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