In some solar system, the distance between planet A and the sun is 2.00 times greater than the distance between planet B and the sun. What is the ratio between 1 year on planet A and 1 year on planet B?

Study Example 12-8.

Example 12-8 The Sun and Mercury The Earth revolves around the Sun once a year at an average distance of 1.50 X 1011 m. (a) Use this information to calculate the mass of the Sun. (b) Find the period of revolution for the planet Mercury, whose average distance from the Sun is 5.79 x 1010 m. Picture the Problem Our sketch shows the orbits of Mercury, Venus, and the Earth in correct proportion. In addition, each of these orbits is slightly elliptical, though the deviation from circularity is too small for the eye to see. Finally, we indicate that the orbital radius for Mercury is 5.79 X 1010 In and the orbital radius for the Earth is 1.50 X 1011 m