A giant star radiates energy at the rate of 3.0 × 1030 W, and its surface temperature has been measured to be 3000 K. Assuming that it is a perfect emitter, what is the radius of this star?(? = 5.67 × 10-8 W/m2 ? K4 )

A) 7.8 × 1010 m
B) 8.7 × 1010 m
C) 1.4 × 1010 m
D) 1.9 × 1011 m
E) 2.3 × 1011 m


E

Physics & Space Science

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