What is characteristic of a main sequence star?

Question

Quizplus · Accepted Answer

A main sequence star is characterized by the fact that the rate of nuclear energy generated in its hydrogen to helium fusing core equals the rate radiated from the surface. This is what allows the star to maintain a stable size and temperature, and falls under the category of thermal equilibrium. The other choices are not necessarily true for all main sequence stars. A main sequence star is a star that is fusing hydrogen into helium in its core. The defining characteristic of a main sequence star is that the rate of nuclear energy generated in the core (through hydrogen fusion) equals the rate of energy radiated from the surface. This equilibrium keeps the star stable and in a state of hydrostatic equilibrium. Mass, rotation, stellar wind, and heavy element production can vary and do not define a main sequence star.

What Is Characteristic of a Main Sequence Star