-A star is observed with a surface temperature of 3,000 K and a luminosity of 10-2 solar. What is the approximate radius of this star?

Question

Quizplus · Accepted Answer

The radius of a star can be estimated using the Stefan-Boltzmann law, which relates the star's luminosity (L), radius (R), and surface temperature (T) in the formula L = 4πR^2σT^4, where σ is the Stefan-Boltzmann constant. Given the star's luminosity is 10^-2 times that of the Sun and its temperature is 3,000 K, we can compare it to the Sun's luminosity and temperature (about 5,800 K) to estimate its radius. A star cooler and less luminous than the Sun will have a smaller radius, making option B (0.3 solar radius) the most reasonable approximation without doing the exact calculation.

-A Star Is Observed with a Surface Temperature of 3,000