## Essential University Physics: Volume 1 (4th Edition)

$5.8 \times 10^3 \ K$
We simplify equation 16.9 to find: $P = (\frac{P}{4 \pi R^2 \sigma})^{1/4}$ $P = (\frac{3.9 \times 10^{26}}{4 \pi (7 \times 10^8)^2(5.7 \times 10^{-8})})^{1/4}= 5.8 \times 10^3 \ K$