Question

The luminosity of the Sun is 4*10^33 erg/s, and its radius is 7*10^10 cm.

What is the Sun's effective temperature in units of Kelvin?

Answer 1

Hi.

(4*10^33) / 4π(2*7*10^10)^2
= 3/(4π*4*7^2) * 10^13
= 0.001218 * 10^12
= 1.218 * 10^9 ..

Hope this helps u!!