A steam pipe with a radius of 2.00 cm, carrying steam at 140oC, is surrounded by a cylindrical jacket with inner and outer radii 2.00 cm and 4.00 cm and made of a type of cork with thermal conductivity 4.00 X 10-2 W /m. K. This in turn is surrounded by a cylindrical jacket made of a brand of Styrofoam with thermal conductivity1.00 X 10-2 W/m €¢ K and having inner and outer radii 4.00 cm and 6.00 cm (Fig. 17.35). The outer surface of the Styrofoam is in contact with air at 15°C. Assume that this outer surface has a temperature of 15°C.
(a) What is the temperature at a radius of 4.00 cm, where the two insulating layers meet?
(b) What is the total rate of transfer of beat out of a 2.00-m length of pipe? (Hint: Use the expression derived in part
(c) Of challenge Problem 17.122.)

6.00 4.00 200 cm cm Steam pipe Cork Styrofoam