Electrical Machines A DC generator beyond critical resistance will generate maximum current. no voltage. maximum power. maximum voltage. maximum current. no voltage. maximum power. maximum voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4, 5 2, 3 ,5 2, 3, 4 1, 2, 3 2, 3, 4, 5 2, 3 ,5 2, 3, 4 1, 2, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor when the length of the air gap is increased, the magnetizing current of the motor increases while the short circuit current __________________. remains unchanged. kept constant to certain value. increased. decreased. remains unchanged. kept constant to certain value. increased. decreased. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Current in a coil undergoing commutation is not able to get reversed completely by the end of commutation period. It is due to reactance voltage induced in the coil. armature emf. coil resistance. None of these reactance voltage induced in the coil. armature emf. coil resistance. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC shunt generator working on load, the brushes are moved forward in the direction of rotation, as a result of this, commutation will improve and terminal voltage will rise . worsen and terminal voltage will fall improve but terminal voltage will fall. worsen and terminal voltage will rise. improve and terminal voltage will rise . worsen and terminal voltage will fall improve but terminal voltage will fall. worsen and terminal voltage will rise. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If Pi and Pc represent core and full load copper loss respectively, the maximum KVA delivered to load corresponding to maximum efficiency is equal to rated KVA is (Pi/Pc)2 √(Pi/Pc) Pc/Pi Pi/Pc (Pi/Pc)2 √(Pi/Pc) Pc/Pi Pi/Pc ANSWER DOWNLOAD EXAMIANS APP
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