Question

Which of the following must occur for a star's core to reach equilibrium after an initial change in fusion rate?

a) If the fusion rate initially increases, then the core expands; If the fusion rate initially decreases, then the core contracts.
b) If the fusion rate initially increases, then the core contracts; If the fusion rate initially decreases, then the core expands.
c) Both increasing and decreasing fusion rates cause the core to expand.
d) Both increasing and decreasing fusion rates cause the core to contract.

Answer 1

For a star's core to reach equilibrium after an initial change in fusion rate, it expands if the fusion rate increases and contracts if the fusion rate decreases.

Step-by-step explanation:

The equilibrium of a star's core after an initial change in fusion rate is essential for the stability of the star. The appropriate response to the question is: a) If the fusion rate initially increases, then the core expands; If the fusion rate initially decreases, then the core contracts. This finding is consistent with the behavior of stellar cores and the process of hydrostatic equilibrium. When the fusion rate increases, the core temperature rises, causing it to expand due to increased pressure. Conversely, if the fusion rate decreases, the core cools and contracts, increasing the pressure and thus the temperature and fusion rate, which restores equilibrium.