申論題

A sphere of radius R and thermal conductivity ky is embedded in an infinite solid of
thermal conductivity ko. The center of the sphere is located at the origin of coordinates
and there is a constant temperature gradient A in the positive z direction far from the
sphere. The temperature at the center of the sphere is .
The steady-state temperature distribution in the sphere T₁ and in the surounding
medium T₀ have been shown to be: