Physics

Problem

Star X has radius

2R_{\odot}

and surface temperature

1.5T_{\odot}

, where

R_{\odot}

and

T_{\odot}

are the Sun’s radius and surface temperature. a. (i) Write an expression for the total power output (luminosity)

L

of a star in terms of its radius

R

and surface temperature

T

. b. (ii) Hence, find the ratio

L_X/L_{\odot}