The magnetic field in the air gap of a two-pole motor has a flux density of 0.8T. The armature is wound with 246 conductors, each of 400mm effective length, mounted at 150mm effective radius, and at full load each conductor carries a current of 20A. Assuming that the actual torque produced is equivalent to that due to two-thirds of the number of conductors cutting the lines of force at right-angles, find (a) the torque in newton metres, and (b) the shaft power developed at 500 rev/min.