A star with the same color as the Sun is found to produces a luminosity 81 times larger. What is its radius compared to the Sun?
1 Answer
May 27, 2018
The star's radius is 9 times our Sun's radius
Explanation:
Luminosity, measured in energy delivered per unit time, is according to the Stefan–Boltzmann equation:
#L= sigma A T^4#
That black body colour is related directly to average temperature is summarised in Wien's Law:
# lambda_("max")=b/T # where#b# is another constant
So
Which means:
For spherical bodies:
The star's radius is 9 times our Sun's