Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.443. 0.573. 0.512. 0.649. 0.443. 0.573. 0.512. 0.649. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For satisfactory performance of 3-phase 480V, 60 Hz induction motor, the supply voltage at 50 Hz should be equal to 400 V. 420 V. 350 V. 480 V. 400 V. 420 V. 350 V. 480 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous generator a synchronous dead load (lamp, furnaces etc) has no ____________ hence it has no natural frequency of oscillation. restoring torque. mechanical rotatory system. damping torque. synchronizing power co efficient. restoring torque. mechanical rotatory system. damping torque. synchronizing power co efficient. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines It is advisable to start a DC series motor with some load to Limit the current. Avoid sparking. Limit the speed. Limit the flux. Limit the current. Avoid sparking. Limit the speed. Limit the flux. 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 coincide with the GNA shift forward by less than 90° shift forward by 90° shift forward by more than 90° coincide with the GNA shift forward by less than 90° shift forward by 90° shift forward by more than 90° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine 4 pole lap winding is used. The number of parallel paths are? 1 4 2 8 1 4 2 8 ANSWER DOWNLOAD EXAMIANS APP
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