If the period of a body's orbit is doubled, then the distance from the host has ___________. Assume the units of period are years and the units of distance are A.U. Choose the best answer.
A)doubled
B)halved
C)stayed the same
D)increased by about 1.5 times

Question

If the period of a body's orbit is doubled, then the distance from the host has ___________. Assume the units of period are years and the units of distance are A.U. Choose the best answer.
A)doubled
B)halved
C)stayed the same
D)increased by  about 1.5 times

Quizplus · Accepted Answer

According to Kepler's third law of planetary motion, the square of the period of an orbit is directly proportional to the cube of the semi-major axis (distance from the host). Therefore, if the period is doubled (2x), the semi-major axis will increase by about 1.5 times (∛2). So, the distance from the host has increased by about 1.5 times.

If the Period of a Body's Orbit Is Doubled, Then