Calculate the temperature of a planet. A star has a surfacetemperature of 4000K and a radius of R = 8 × 108 m It has a rocky,airless planet orbiting it at a distance of 1.0×1011 meters. Theplanet has a radius of 5.0 × 106 m. We will estimate 1 for allobjects. (a) What is the total power output of the star?
(b) What is the power incident on each square meter at distanceto the planet (i.e. on an imaginary sphere).
(c) How much power is absorbed by the planet? (Assume the planetis black. Use the fact that the planet looks like a disk.)
(d) In equilibrium, Pin = Pout. How much power does the planetradiate per square meter of surface area of the planet?
(e) What is the temperature of the planet? (Should humans try tolive there?)
