Question

An uncoated, solid cable of length L- 1 m and diameter D = 40 mm is exposed to convection conditions characterized by h = 55 W/m2-K and Too = 20°C. Determine the maximum electric current that can be carried by the cable if it is pure copper in A. The electrical resistivity is Re - 10 x 10-8 0 m for copper at it's melting points.

Fig: 1