Two circular disks are parallel and directly facing each other. The disks are diffuse, but their emissivities vary with wavelength. The properties are approximated with step functions as shown. The...

Two circular disks are parallel and directly facing each other. The disks are diffuse, but their emissivities vary with wavelength. The properties are approximated with step functions as shown. The disks are maintained at temperatures T1=1200 K and T2=800 K. The surroundings are at Te=400 K. Compute the rate of energy that must be supplied to or removed from the disks to maintain their specified temperatures. The outer surfaces of the disks are insulated so there is radiation interchange only from the inner surfaces that are facing each other.