Immediately following the end of core hydrogen fusion, continued energy flow from the core is created by:
A)helium fusion.
B)the Kelvin-Helmholtz contraction.
C)radioactivity.
D)the fusion of carbon, oxygen, and other heavier nuclei.

Question

Quizplus · Accepted Answer

After core hydrogen fusion is exhausted, the core contracts under gravity and releases gravitational potential energy as thermal energy through the Kelvin-Helmholtz contraction. This contraction causes the core to heat up and start helium fusion, and energy flow from this fusion takes over as the new energy source for the star.

Immediately Following the End of Core Hydrogen Fusion, Continued Energy