What will be the intrinsic brightness or luminosity of a white dwarf star that has the same temperature as the Sun? (See Figure 10-7,Comins,Discovering the Universe,6th ed.)
A) 4 times the Sun's luminosity
B) Because it has the same surface temperature, the white dwarf will have the same brightness.
C) 10-² of the Sun's luminosity
D) 10-⁴ of the Sun's luminosity

Question

Quizplus · Accepted Answer

The luminosity of a star is directly related to its surface area and temperature. Since a white dwarf has a much smaller surface area than the Sun, even at the same temperature, its intrinsic brightness or luminosity will be much lower. According to Figure 10-7, a white dwarf with the same temperature as the Sun would have a luminosity of about 10^-4 times that of the Sun.

What Will Be the Intrinsic Brightness or Luminosity of a White