Electrical Machines Iron losses in a DC machine are independent of variation in speed and voltage. load. voltage. speed. speed and voltage. load. voltage. speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated voltage. If the speed has to be brought down to 0.25 p.u. the supply voltage has to be approximately brought down to 0.125 p.u 0.25 p.u 0.75 p.u 0.5 p.u 0.125 p.u 0.25 p.u 0.75 p.u 0.5 p.u ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer maximum flux density is not constant, the eddy current loss varies as V² f² f V V² f² f V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc generator operating on load with its brushes on the geometrical neutral axis (GNA), the magnetic neutral axis (MNA) is shifted in the direction of rotation. Now, if the brushes are given a lead of 90° (electrical), then the MNA will shift forward by more than 90° shift forward by less than 90° shift forward by 90° coincide with the GNA shift forward by more than 90° shift forward by less than 90° shift forward by 90° coincide with the GNA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of DC motor Back emf increase but line current falls. Both back emf as well as line current fall. Back emf falls and line current increase. Both back emf as well as line current increase. Back emf increase but line current falls. Both back emf as well as line current fall. Back emf falls and line current increase. Both back emf as well as line current increase. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor has which of the following characteristics? Has a almost constant speed. Has a poor torque. Has its field winding consinting of thick wire and less no of turns. Can be started easily without load. Has a almost constant speed. Has a poor torque. Has its field winding consinting of thick wire and less no of turns. Can be started easily without load. ANSWER DOWNLOAD EXAMIANS APP
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