An uncoated, solid cable of length L = 1m and diameter D = 40 mm is exposed to convection conditions characterized by h = 55 W/m2 ·K and T[infinity] = 20°C. Determine the maximum electric current that ca be carried by the cable if it is pure copper, pure aluminum, or pure tin. Calculate the minimum wire temperatures. The electrical resistivity is Re = 10 x 10-8 Ω·m for copper and aluminum at their melting points, while the electrical resistivity of tin is Re = 20 x 10-8 Ω·m at its melting point

Apump is used to circulate hot water in a home heating system. water enters the well-insulated pump operating at steady state at a rate of 0.42 gal/min. the inlet pressure and temperature are 14.7 lbf/in.2, and 180°f, respectively; at the exit the pressure is 60 lbf/in.2 the pump requires 1/15 hp of power input. water can be modeled as an incompressible substance with constant density of 60.58 lb/ft3 and constant specific heat of 1 btu/lb or. neglecting kinetic and potential energy effects, determine the temperature change, in °r, as the water flows through the pump.