What is the source of the energy radiated by a white dwarf?
A)the proton-proton chain
B)the CNO cycle
C)gravitational contraction after becoming a white dwarf
D)gravitational contraction during the white dwarf formation phase

Question

Quizplus · Accepted Answer

The source of energy radiated by a white dwarf is gravitational contraction during the white dwarf formation phase. As the core of the star collapses during this phase, it releases a large amount of energy in the form of heat and light. The energy is then radiated away from the surface of the white dwarf, keeping it hot and luminous. The other options (A and B) are related to nuclear reactions which are not involved in the energy source of a white dwarf. Option C is incorrect because gravitational contraction has already occurred to form the white dwarf, and it is not a ongoing process.

What Is the Source of the Energy Radiated by a White