Electrical Machines The power flow of a dc motor, with respect to a DC generator is increased. modified. none of these. reversed. increased. modified. none of these. reversed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The introduction of interpoles in between the main poles improves the performance of a dc machine, because the inequality of air-gap flux on the top and bottom halves of the armature is removed the flux waveform is improved with reduction in harmonics the interpoles produce additional flux to augment the developed torque a counter-emf is induced in the coil undergoing commutation the inequality of air-gap flux on the top and bottom halves of the armature is removed the flux waveform is improved with reduction in harmonics the interpoles produce additional flux to augment the developed torque a counter-emf is induced in the coil undergoing commutation ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An 8 pole DC generator has 500 armature conductors and useful flux per pole of 0.065 Wb. What will be the emf generated if it is lap connected and runs at 1000 rpm. What must be the speed at which it is driven to produce the same emf if it is wave wound? 541.67V, 250 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. 2166.67V, 230 rpm. 541.67V, 250 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. 2166.67V, 230 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 V, 50 Hz, 4 pole single phase induction motor is rotating in the clockwise ( forward ) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8 Ω. Then the effective rotor resistance in the backward branch of the equivalent circuit will be 8 Ω. 4 Ω. 10 Ω. 2 Ω. 8 Ω. 4 Ω. 10 Ω. 2 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? 120 / PN Hz. PN / 2 Hz. 120P / N Hz. 120N / P Hz. 120 / PN Hz. PN / 2 Hz. 120P / N Hz. 120N / P Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of rotating magnetic field of 8 pole 50 Hz induction motor is 750 rpm 3000 rpm 1500 rpm 1000 rpm 750 rpm 3000 rpm 1500 rpm 1000 rpm ANSWER DOWNLOAD EXAMIANS APP
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