As the early Sun got smaller in a Kelvin-Helmholtz contraction, its interior became hotter and gained thermal energy. What was the source of this energy?

Question

Quizplus · Accepted Answer

The source of the energy was the gravitational potential energy released as the Sun contracted. As the material fell inward, it converted potential energy into thermal energy, heating up the Sun's interior.

As the Early Sun Got Smaller in a Kelvin-Helmholtz Contraction