2–90 Reconsider Problem 2–89. Using the relation obtained
for the variation of temperature in the
sphere, plot the temperature as a function of the radius r in the
range of r = 0 to r = r0. Also, plot the center temperature of
the sphere as a function of the thermal conductivity in the
range of 10 W/m · °C to 400 W/m · °C. Discuss the results. Use
the EES (or other) software.