Electrical Machines A transformer has resistance and reactance in per unit as 0.01 and 0.04 respectively. Its voltage regulation for 0.8 power factor lagging and leading will be 4.8% and -3.2% 3.2% and -1.6% 6% and -4% None of these 4.8% and -3.2% 3.2% and -1.6% 6% and -4% None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 2, 3 1, 4 1, 3 2, 4 2, 3 1, 4 1, 3 2, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two 3-phase AC generators are such that one has twice the linear dimensions of the other. The field windings of each are excited to give identical sinusoidal air-gap flux density waveform. Both have the same number of stator slots and identical winding patterns. The conductor/slot in a big generator is K times that of the smaller one. The value of K to get equal no load voltage at same frequency is 1/4. 8. 1/2. 4. 1/4. 8. 1/2. 4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes 1/4 of the intial value twice the initial value 4 time the initial value 1/2 of the initial value 1/4 of the intial value twice the initial value 4 time the initial value 1/2 of the initial value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Example of double excited machine is DC Shunt Motor Both are correct. Synchronous motor. None of these DC Shunt Motor Both are correct. Synchronous motor. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - φ induction motor running at full load which of these parameters is stationary with respect to the stator mmf wave? Both rotor and stator winding. Rotor mmf wave. Rotor winding. Stator winding. Both rotor and stator winding. Rotor mmf wave. Rotor winding. Stator winding. ANSWER DOWNLOAD EXAMIANS APP
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