Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 1, 2 and 3 1, 3 3 only 1, 2, 3 and 4 1, 2 and 3 1, 3 3 only 1, 2, 3 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation is increased, the power factor is leading power factor lagging power factor unity power factor None of these leading power factor lagging power factor unity power factor None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The material used for commutator brushes is mostly mica. copper. carbon. cast iron. mica. copper. carbon. cast iron. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the reactance voltage when current is changed from -2A to 2A in 4 sec and self inductance is 1H? 2 V 4 V 1 V 0 V 2 V 4 V 1 V 0 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC compound motor the field regulator is provided to control the field flux. limit the armature current. demagnetize the field partially. control the armature flux. control the field flux. limit the armature current. demagnetize the field partially. control the armature flux. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If a DC motor is connected across the AC supply it will Run at lower speed. Run at normal speed. Burn. Not run. Run at lower speed. Run at normal speed. Burn. Not run. ANSWER DOWNLOAD EXAMIANS APP
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