A small surface of area A1 = 3 cm2 and a radiation sensor of area A2 = 1 cm2 are oriented...

A small surface of area A1 = 3 cm2 and a radiation sensor of area A2 = 1 cm2 are oriented as shown in the figure. Surface A1 is opaque (diffuse emitter and reflector) and maintains a constant temperature of T1 = 400 K. The absorptivity and emissivity of surface A1 are 0.5 and 0.7, respectively. If surface A1 is experiencing 2000 W/m2 of irradiation, determine the rate at which radiation emitted from A1 is intercepted by the sensor.

FIGURE P12-126