If Earth had twice its present mass but it orbited at the same distance from the sun as it does now, its orbital period would be
A) 6 months.
B) 2 years.
C) 1 year.
D) 3 years.
E) 4 years.

Question

Quizplus · Accepted Answer

The orbital period of a planet around the sun is determined by its distance from the sun, not its mass. According to Kepler's third law, the square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit. Since the distance from the sun is unchanged, the orbital period remains 1 year.

If Earth Had Twice Its Present Mass but It Orbited