Question

As observed from the earth, the sun appears to move in an approxite circular orbit. For the motion of another planet like mercury as observed from the earth, this would
A. be similarly true
B. not be true because the force between the earth and mercury is not inverse square law
C. not be true because the major gravitational force on mercury is due to the sun
D. not be true because mercury is influenced by forces other than gravitational forces

Answer 1

Correct Answer - C
As observed from the earth, the sun appears to move in an approximate circular orbit. The gravitational force of attraction between the earth and the sun always follows inverse square law. Due to relative motion between the earth and mercury, the orbit of mercury, as observed from the earth will not be approximately circular, since the major gravitational force on mercury is due to the sun.