What is the Formula for Determining the luminosity of a star?

What is the equation/Formula for finding the luminosity of a star in Solar Luminosities?

Please explain clearly and write what each letter represents

say a star was 5 time larger than the sun and it had a temperature of 8,000 kelvin, what would be the luminosity of this stars is L_sun?What is the Formula for Determining the luminosity of a star?The formula for the Luminosity L = Area * Energy Flux = 4pi R^2 * sigma T^4, where R is the radius and T the temperature. The second factor is of course the Stefan-Boltzman law.



As my computer doesn't like Greek letters, and because I always forget the values of these pesky constants, I prefer to write: L/L_Sun = (R/R_Sun)^2 (T/T_Sun)^4



In this case L/L_Sun= 5^2 (8000/5780)^4 = 91.7



So L = 91.7 L_Sun.What is the Formula for Determining the luminosity of a star?Mass-Luminosity Equation:

Luminosity and mass turn out to be directly proportional. A star's luminosity (in solar luminosity) is equal to its mass (in solar masses) to the power 3.5: L = M^3.5.



Five times larger? Diameter? Mass?

Temperature vs Luminosity: Stefan-Boltzman Law

L = 4 pi R2 (star's surface area)

X sigma T4 (energy emitted by 1 sq. meter)



You do the math, I am not good at it.What is the Formula for Determining the luminosity of a star?Luminosity means the total energy radiated by a body (star) per second. Luminosity is L= Flux x Area of a body. Assuming that 5 times larger than the Sun means 5 times the surface of the Sun, you get:



L_star = 5 x Solar surfaces x sigma x (8000)^4.



sigma = Stefan Boltzmann constant 5.67x10^(-12)

sigma x (T)^4 means energy radiated per second per unit area by a body at temperature T.



L_star= 4pi x (R_star)^2 x sigma x (T_star)^4.



Where R_star = Radius of the star. T_star = Temperature of the star.



You need to know the output of the sun or the temperature of the sun for this problem though.