Un alambre de cobre que tiene un dimetro de 3/16 in se asla con una capa de 4 in de un material que tiene una conductividad trmica de 0.14 Btu/h ft F. La superficie exterior del aislante se mantiene a 70 F. Qu cantidad corriente puede pasar a travs del alambre si la temperatura mxima del aislante se limita a 120 F la resistividad del cobre es 1.72*10^-6 ohm-cm

A copper wire that has a diameter of 3/16 in. is insulated with a 4-in. layer of a material that has a thermal conductivity of 0.14 Btu/h ft F. The outer surface of the insulation is maintained at 70F. What amount of current can pass through the wire if the maximum temperature of the insulator is limited to 120F and the resistivity of copper is 1.72*10-6 ohm-cm