In a semidetached binary star system:
A)the stars share the same outer atmosphere, but the cores of the two stars do not touch.
B)one star fills its Roche lobe, while the other does not.
C)one star orbits the center of mass, while the other moves freely through space.
D)both stars fill their Roche lobes.

Question

Quizplus · Accepted Answer

In a semidetached binary star system, one star fills its Roche lobe while the other does not. The Roche lobe is the region around a star within which material is gravitationally bound to that star, and in a binary system, each star has its own Roche lobe. When one star fills its Roche lobe, material can transfer from that star to the other star, leading to potential interactions and evolutionary changes in both stars.

In a Semidetached Binary Star System