An artificial satellite carries electronic equipment that continuously produces of…
PHYSICS · Subjective · A Level · Physics · Further mechanics and thermal physics · Further mechanics and thermal physics
Problem
An artificial satellite carries electronic equipment that continuously produces 4.0kW of waste heat. To maintain proper functioning, a flat radiator panel on the outside of the satellite must dissipate this energy by thermal radiation. Assume the panel acts as a perfect black surface and is to be maintained at a steady temperature of 320K.
(i) Derive an expression for the minimum surface area A of the radiator required to dispose of a steady power P at temperature T.
(ii) Using the expression, calculate the numerical value of A needed for P=4.0kW at T=320K.
(iii) If mission constraints later require the operating temperature of the panel to be lowered to 280K while the waste power remains the same, by what factor must the surface area be increased?