What affects the average orbital speed of a star in our galaxy?
A)the mass of the galaxy inside its orbit and the size of its orbit
B)the star's mass and the mass of the galaxy
C)the mass and age of the star
D)the mass and age of the galaxy

Question

Quizplus · Accepted Answer

The average orbital speed of a star in our galaxy is primarily determined by the mass of the galaxy inside its orbit (because that affects gravity) and the size of its orbit (larger orbits have slower speeds). The star's mass and the mass of the galaxy can also play a role, but they are not as significant as the first two factors. The mass and age of the star and the mass and age of the galaxy are not directly related to the star's orbital speed.

What Affects the Average Orbital Speed of a Star in Our