One of them will cancel the RMF of the main winding and the other will get added up.
Stator is also provided with a 'starting winding' which is used only for starting purpose.But one big problem remains; how to provide such an initial rotation to the rotor ? Nikola Tesla, a famous Yugoslav inventor suggested one ingenious solution to this problem.If we can cancel any of the rotating fields, we will be able to start the motor.as power delivered to most of the houses and offices is single phase.In addition to this, single phase motors are reliable, cheap in cost, simple in construction and easy to repair.
Principle of operation of single phase capacitor start induction motor
This can be understood from the schematic of single phase induction motor at the left.When the stator of a single phase motor is fed with single phase supply, it produces alternating flux in the stator winding.The rotor is the rotating part, the stator winding helps in rotating the rotor.In Fig.1 the iron layer lamina which is fitted inside rotor is not shown, for better viewing of the rotor bars.The effect of the rotating magnetic field on the rotor is interesting.