Electrical Machines The polarity of a DC generator can be reversed by reversing field electric current as well as direction of rotation. increasing field current. any of above. reversing the field current. reversing field electric current as well as direction of rotation. increasing field current. any of above. reversing the field current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the back emf in DC motor vanishes suddenly the motor will start haunting. burn. run at very low speed. run at very high speed. start haunting. burn. run at very low speed. run at very high speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Under which of the following conditions is a dc motor provided with compensating winding used ? 1. Wide range of speed control above normal 2. Wide range of steady load variation with no speed control 3.Wide range of rapid variation in load Select the correct answer using the codes given below : Codes : 1, 2 and 3 1 and 2 1 and 3 2 and 3 1, 2 and 3 1 and 2 1 and 3 2 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The maximum possible speed at which an alternator can be driven to generate 50 Hz and 4000 V is 1500 rpm. 3000 rpm. 3600 rpm. 4000 rpm. 1500 rpm. 3000 rpm. 3600 rpm. 4000 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A flat compound generator is obtained from compound generator by connecting a variable resistor in series with the series field in series with the shunt field in parallel with the shunt field in parallel with the series field in series with the series field in series with the shunt field in parallel with the shunt field in parallel with the series field ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of a DC motor back emf falls and line current increases. both back emf as well as line current increase. both back emf as well as line current fall. back emf increases but line current falls. back emf falls and line current increases. both back emf as well as line current increase. both back emf as well as line current fall. back emf increases but line current falls. ANSWER DOWNLOAD EXAMIANS APP
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