A 3-phase induction motor runs at a speed of 1485 rpm at no-load and at 1350 rpm at fullload when supplied from a 50-Hz, 3-phase line.
(a) How many poles does the motor have?
(b) What is the % slip at no-load and at fullload?
(c) What is the frequency of rotor voltages at no-load and at full-load? (d) What is the speed at both no-load and fullload of: (i) the rotor field with respect to rotor conductors, (ii) the rotor field with respect to the stator, and (iii) the rotor field with respect to the stator field.