Electrical Machines Motors for fans and pumps are selected in the rpm range 1440 to 2880. 375 to 500. 720 to 920. 500 to 720. 1440 to 2880. 375 to 500. 720 to 920. 500 to 720. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The condition for maximum running torque is 0.707 lagging zero R = S.X 0.5 lagging unity 0.707 lagging zero R = S.X 0.5 lagging unity ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor speed of an induction motor is given by None of these Ns = 120f / p × ( 1 - s ). Ns = 120f /p × ( 1 - r). Nr = 120f / p × (1-s). None of these Ns = 120f / p × ( 1 - s ). Ns = 120f /p × ( 1 - r). Nr = 120f / p × (1-s). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the load current and the flux of a DC motor are held constant and voltage applied across its armature is increased by 5%, the speed of the motor will increase by 5 %. remain unchanged. depend on other factors. reduce by 5 %. increase by 5 %. remain unchanged. depend on other factors. reduce by 5 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the number of rotor slots is equal to number of stator slots, then motor refuses to start. Hence it is known as crawling. cogging. relative speed. air gap. crawling. cogging. relative speed. air gap. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer maximum flux density is not constant, the eddy current loss varies as V V² f² f V V² f² f ANSWER DOWNLOAD EXAMIANS APP
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