Electrical Machines Find the developed torque DC Series Motor having armature resistance of 0.2 Ω and taking armature current of 60 A is connected to 250 V supply. Considered brush drop of 1 V each. 133.22 N-m 234.76 N-m. 266.20 N-m. cant be determined. 133.22 N-m 234.76 N-m. 266.20 N-m. cant be determined. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following methods of speed control is not affected through stator side? Change of supply voltage. Change of supply frequency. Change of number of pole. Change of rotor resistance. Change of supply voltage. Change of supply frequency. Change of number of pole. Change of rotor resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the mechanical power developed by a DC series motor is maximum? None of above. Back emf is equal to zero. Back emf is equal to applied voltage. Back emf is equal to half the applied voltage. None of above. Back emf is equal to zero. Back emf is equal to applied voltage. Back emf is equal to half the applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are the advantages of carbon brush over the copper brush? In case of any sparking they will be less damaged than copper brushes All of these They are not hard as copper brush They are self lubricating in nature In case of any sparking they will be less damaged than copper brushes All of these They are not hard as copper brush They are self lubricating in nature ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. What is the slip value? 0.02 0.4 0.2 0.04 0.02 0.4 0.2 0.04 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To avoid formation of grooves in the commutator the brushes of same polarity should track each other. brush position has no effect on the commutator grooving. the brushes of opposite polarity should track each other. None of these the brushes of same polarity should track each other. brush position has no effect on the commutator grooving. the brushes of opposite polarity should track each other. None of these ANSWER DOWNLOAD EXAMIANS APP