In a binary star system that contains stars with 10 M¤ and 5 M¤,the velocity of the 10 M¤ star will be ________ times the velocity of the 5 M¤ star.

Question

Quizplus · Accepted Answer

According to Kepler's Third Law, the period of revolution of a star in a binary system is proportional to the radius of its orbit. Since both stars in this binary system are under the same gravitational influence and revolve around their mutual center of mass, the ratio of their velocities will be the inverse of the ratio of their masses. Therefore, the velocity of the 10 M¤ star will be half of the velocity of the 5 M¤ star, i.e., it will be 0.5 times the velocity of the 5 M¤ star.

In a Binary Star System That Contains Stars with 10