A solid cylinder of radius r1 = 2.9 cm, length h1 = 5.5 cm, emissivity 0.72, and temperature 38°C is suspended in an environment of temperature 47°C. (a) What is the cylinder's net thermal radiation transfer rate P1? (b) If the cylinder is stretched until its radius is r2 = 0.50 cm, its net thermal radiation transfer rate becomes P2. What is the ratio P2/P1?
A) P1 = 3.54 W, P2/P1 = 0.50
B) P1 = 7.08 W, P2/P1 = 0.25
C) P1 = 10.62 W, P2/P1 = 0.75
D) P1 = 14.16 W, P2/P1 = 1.00