A long cylinder has its surface maintained at 135C and is buried in a material having a

Question:

A long cylinder has its surface maintained at 135ºC and is buried in a material having a thermal conductivity of 15.5 W/m· ºC. The diameter of the cylinder is 3 cm and the depth to its centerline is 5 cm. The surface temperature of the material is 46ºC. Calculate the heat lost by the cylinder per meter of length.