1.A 440 -V shunt motor has armature resistance of 0.8 ohm and field resistance of 200 ohm . determine the back emf when giving an output of 7.64 KW at 85% efficiency ?
2.A short 60mm diameter circle bar is made of material for which the maximum safe compressive strees is 80 MPa and the maximum safe shearing strees is 30 MPa. determine the maximum axial compressive force that can be safely applied to the bar ?