Consider a long resistance wire of radius r1 = 0.3 cm and thermal conductivity kwire = 18...

Consider a long resistance wire of radius r1 = 0.3 cm and thermal conductivity kwire = 18 W/m · K in which heat is generated uniformly at a constant rate of ėgen = 4.8 W/cm3 as a result of resistance heating. The wire is embedded in a 0.4-cm-thick layer of plastic whose thermal conductivity is kplastic = 1.8 W/m · K. The outer surface of the plastic cover loses heat by convection to the ambient air at T∞= 25 °C with an average combined heat transfer coefficient of h - 14 W/m2 · K. Assuming one-dimensional heat transfer, determine the temperatures at the center of the resistance wire and the wire-plastic layer interface under steady conditions. Answers: 255.7°C, 266.3°C