Electrical Machines A 3-phase, alternator has generated emf per phase of 230 V with 10% 3rd harmonic and 6% 5th harmonic content. Calculate rms line voltage for star connection. 230.2 V. 100 V. 50 V. 399 V. 230.2 V. 100 V. 50 V. 399 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated) changes to 1.5 times the original value changes to three times the original value remain the same as the original changes to 0.5 times the original value changes to 1.5 times the original value changes to three times the original value remain the same as the original changes to 0.5 times the original value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The overall power factor of an on load transformer depends on the power factor of the load. is always lagging. is always leading. is always unity. depends on the power factor of the load. is always lagging. is always leading. is always unity. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, the space distribution of air-gap flux density wave at no load is co- sinusoidal sinusoidal rectangular flat-topped co- sinusoidal sinusoidal rectangular flat-topped ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A single-phase transformer has its maximum efficiency at 60 percent of full load. At full load copper loss will be zero. less than core loss. more than core loss. equal to core loss. zero. less than core loss. more than core loss. equal to core loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt generator, when driven without any excitation, showed an open circuit voltage of 12 V. When the field winding was excited, the voltage dropped to zero. It happened because there was a break in the armature circuit field resistance was higher than critical resistance field winding was wrongly connected there was no residual magnetism in the field circuit there was a break in the armature circuit field resistance was higher than critical resistance field winding was wrongly connected there was no residual magnetism in the field circuit ANSWER DOWNLOAD EXAMIANS APP
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