Chapter 12, Problem 12.83P

A small anodized aluminum block at ${35}^{\circ }C$ is heated in a large oven whose walls are diffuse and gray with $\epsilon =0.85$ and maintained at a uniform temperature of ${175}^{\circ }C$ . The anodized coating is also diffuse and gray with $\epsilon =0.92$ . A radiation detector views the block through a small opening in the oven and receives the radiant energy from a small area, referred to as the tar- get, At, on the block. The target has a diameter of 3mm, and the detector receives radiation within a solid angle 0.001 sr centered about the normal from the block.

(a) If the radiation detector views a small, but deep, hole drilled into the block, what is the total power (W) received by the detector?

(b) If the radiation detector now views an area on the block surface, what is the total power (W) received by the detector?