Newton's reformulation of Kepler's third law allows us to measure the masses of bodies in orbit around each other, if we can measure:
A) the rotation rate of each object
B) the distances and periods of revolution
C) the eccentricities and semi-major axes
D) the force and the reaction force
E) the sweetness of those fig-filled cookie bars

Question

Quizplus · Accepted Answer

Kepler's third law states that the square of the period of revolution of a planet is proportional to the cube of its average distance from the sun. Newton's reformulation of this law relates the masses of the two bodies in orbit to their distance and period of revolution. Therefore, if we know the distances and periods of revolution, we can use Newton's reformulation to measure the masses of the bodies in orbit around each other.

Newton's Reformulation of Kepler's Third Law Allows Us to Measure