Which of the following effects would stop novas occurring on a white dwarf for a period of tens of millions of years?
A) the white dwarf's interior cooling to low temperatures
B) the white dwarf's companion evolving onto the horizontal branch
C) the white dwarf undergoing a thermonuclear runaway on its surface
D) the white dwarf becoming tidally locked to its companion

Question

Quizplus · Accepted Answer

Novas occur on white dwarfs in binary systems because they accrete material from their companion star. If the companion star evolves onto the horizontal branch, it will no longer transfer material to the white dwarf, leading to a cessation of nova activity. The other choices do not necessarily stop novas on a white dwarf for a long period of time.

Which of the Following Effects Would Stop Novas Occurring on a White