Electrical Machines With the increase in speed of a DC motor back emf falls and line current increases. back emf increases but line current falls. both back emf as well as line current increase. both back emf as well as line current fall. back emf falls and line current increases. back emf increases but line current falls. both back emf as well as line current increase. both back emf as well as line current fall. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In double cage induction motor, the inner cage offers high resistance and high reactance. high resistance and low reactance. low resistance and low reactance. low resistance and high reactance. high resistance and high reactance. high resistance and low reactance. low resistance and low reactance. low resistance and high reactance. 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 interpoles produce additional flux to augment the developed torque a counter-emf is induced in the coil undergoing commutation the flux waveform is improved with reduction in harmonics the inequality of air-gap flux on the top and bottom halves of the armature is removed the interpoles produce additional flux to augment the developed torque a counter-emf is induced in the coil undergoing commutation the flux waveform is improved with reduction in harmonics ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 3 1, 4 2, 4 1, 3 2, 3 1, 4 2, 4 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a step down transformer which one of the following statements is true? Secondary current is less than primary current. Secondary power is less than primary power. Number of secondary turns is less than primary turns. Number of secondary turns is more than that of primary. Secondary current is less than primary current. Secondary power is less than primary power. Number of secondary turns is less than primary turns. Number of secondary turns is more than that of primary. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In alternator, the rotary part is magnetic field poles. none of these. armature. core. magnetic field poles. none of these. armature. core. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS