An astrophysicist determines the total power P P\,P radiated by a spherical star using the Stefan-Boltzmann law:
P=4πR2σT4 P = 4 \pi R^2 \sigma T^4 P=4πR2σT4where R R\,R is the radius of the star, T T\,T is its surface temperature, and σ \sigma\,σ is the Stefan-Boltzmann constant.
The percentage uncertainty in the measurement of R R\,R is 2.4% and the percentage uncertainty in the measurement of T T\,T is 1.5%. The uncertainty in σ \sigma\,σ is negligible.
What is the percentage uncertainty in the calculated power PPP?
3.9%3.9\%3.9%
7.8%7.8\%7.8%
10.8%10.8\%10.8%
12.6%12.6\%12.6%