6.5 H.P., 50-Hz, 3-phase, 440 V, induction motors are available for the following r.p.m. Which motor will be the costliest ?

7.In three-phase induction motors sometimes copper bars are placed deep in the rotor to

8.The starting torque of a 3-phase squirrel cage induction motor is

9.The stating torque of the slip ring induction motor can be increased by adding

10.The power scale of circle diagram of an induction motor can be found from