Electrical Machines The polarity of a DC generator can be reversed by reversing field electric current as well as direction of rotation. any of above. reversing the field current. increasing field current. reversing field electric current as well as direction of rotation. any of above. reversing the field current. increasing field current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If peak value of phase mmf is F max , then peak value of the rotating field caused by three phase is Fmax. (3/2)Fmax. (1/2)Fmax. 3Fmax. Fmax. (3/2)Fmax. (1/2)Fmax. 3Fmax. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage to a dc machine is 230 V, then the back emf, for maximum power developed, is 200 V 230 V 460 V 115 V 200 V 230 V 460 V 115 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt generator builds up to a voltage of 220 V at no load while running at its rated speed. If the speed of the generator is raised by 25% kepping the circuit conditions unaltered, then the Voltage to which the machine would build up will increase to 1.25 times 220 V increase to a value greater than 1.25 times 220 V increase to value lying between 220 V and 1.25 times 220 V not change and remain at 220 V increase to 1.25 times 220 V increase to a value greater than 1.25 times 220 V increase to value lying between 220 V and 1.25 times 220 V not change and remain at 220 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a transformer to be tested at full load conditions but consuming only losses from the main, we do OC and SC tests None of these back to back test load test OC and SC tests None of these back to back test load test ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines During no load test, an induction motor draws power for copper loss and windage friction loss. for core loss and copper loss. only for the small copper loss. for core loss and windage and friction loss. for copper loss and windage friction loss. for core loss and copper loss. only for the small copper loss. for core loss and windage and friction loss. ANSWER DOWNLOAD EXAMIANS APP
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