Two rectangular copper bus bars, each 1/4 in. thick × 4 in. wide with facing flats, are separated by a 1/2-in. space between the flats. Determine per foot run of bus bars:

(1) The resistance and leakage inductance at 75°C and

(2) The mechanical force under a fault current of 50-kA peak, assuming the bar shape factor K = 0.7.