Why is there a main sequence mass-luminosity relation?
A)because helium fusion produces carbon
B)because more massive stars support their larger weight by making more energy
C)because the helium flash occurs in degenerate matter
D)because all stars on the main sequence have about the same radius

Question

Quizplus · Accepted Answer

The main sequence mass-luminosity relation states that more massive stars have a higher luminosity than less massive stars. This is because more massive stars have a larger gravitational force that requires more energy to generate pressure and keep the star from collapsing, leading to more energy being produced through fusion reactions. Therefore, the larger weight of more massive stars is supported by making more energy.

Answer: D
 All stars on the main sequence have a similar structure, with the energy generated mainly in the core through hydrogen fusion. Because of this, they all have roughly the same radius, which leads to a correlation between mass and luminosity. However, while this is a contributing factor to the main sequence mass-luminosity relation, it is not the main reason for it.

Why Is There a Main Sequence Mass-Luminosity Relation