Electrical Machines In a 3-phase induction motor, if the supply voltage and frequency are reduced by the same ratio, then slip at which maximum torque occurs is less and maximum torque increases more and maximum torque remains constant less and maximum torque decreases more and maximum torque decreases less and maximum torque increases more and maximum torque remains constant less and maximum torque decreases more and maximum torque decreases ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-φ alternator has negligible stator resistance. A short circuit test is conducted on this alternator. At a particular speed, a field current of If1 is required to drive the rated armature current. If the speed of the alternator is reduced to half, the field current required to maintain rated armature current Cannot be predicted due to insufficient data. Would be equal to If1/2. Woud be equal to 2If1. Would be equal to If1. Cannot be predicted due to insufficient data. Would be equal to If1/2. Woud be equal to 2If1. Would be equal to If1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For the purpose of starting an induction motor, star/delta switch is an equivalent to auto transformer of ratio 66.3% 57.7% 33.3% 50% 66.3% 57.7% 33.3% 50% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by a 220 V DC series motor of armature resistance 0.5 Ω and back emf of 200 V is 44 A. 400 A. 40 A. 440 A. 44 A. 400 A. 40 A. 440 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor winding for a 3-phase slip-ring induction motor having delta-connected stator must be connected in delta. delta or star according to need. star. None of these delta. delta or star according to need. star. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the armature current of 5 Amp is flowing through the dc motor the torque produced is 47 Nm. Keeping the speed constant if the armature current is increased to 7 amp, calculate the new torque. Assume losses to be constant. 65.8 Nm. 74 Nm. 27.73 Nm . 38.5 Nm. 65.8 Nm. 74 Nm. 27.73 Nm . 38.5 Nm. ANSWER DOWNLOAD EXAMIANS APP