- Venus is a planet in the Solar System. The following data are given:
Orbital period of Venus = 225 days
Orbital period of Earth = 365 days
(a) Calculate the ratio (orbital radius of Venus) / (orbital radius of Earth). [2]
(b) Explain how observations of the motion of the planets allow scientists to determine the mass of the Sun. [2]
(c) The difference between the maximum and minimum Earth–Sun distances is 5.0 × 10⁹ m. The difference in gravitational potential due to the Sun between these positions is 3.0 × 10⁷ J kg⁻¹.
Estimate the average gravitational field strength due to the Sun at the position of Earth. [2]