Electrical Machines The brush-axis of a bipolar dc motor is rotated by 90°. The effect of this rotation on the back emf Eband the torque developed Tdwould be such that Eb is unchanged, but Td is zero Eb is zero, but Td is unchanged both Eb and Td are unchanged both Eb and Td are zero Eb is unchanged, but Td is zero Eb is zero, but Td is unchanged both Eb and Td are unchanged both Eb and Td are zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 ,V 15 , kW 100 rpm shunt motor with armature resistance of 0.25 , W has a rated line current of 68 A and a rated field current of 2.2 A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8 A and a field current of 1.8 A is 36.36% increase 18.18% increase 36.36% decrease 36.36% increase 36.36% increase 18.18% increase 36.36% decrease 36.36% increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 12 pole, 600 V, 50 Hz star connected IM has rotor resistance and stand still resistance of 0.03 Ω and 0.5 Ω respectively. The speed of maximum torque will be 240 rpm. 450 rpm. 540 rpm. 470 rpm. 240 rpm. 450 rpm. 540 rpm. 470 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In travelling cranes for hoisting and lowering which type of motor is preferred? AC slip ring motor. Synchronous motor. Single phase induction motor. DC series motor. AC slip ring motor. Synchronous motor. Single phase induction motor. DC series motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a specific open-circuit voltage of a DC generator, the short-circuit electric current will be maximum when it is differentially compounded. cumulatively compounded. shunt connected. separately excited. differentially compounded. cumulatively compounded. shunt connected. separately excited. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC motor with armature resistance of 0.5 ohms connected directly to a 220 Volt supply. If the armature is stationary then the current flowing through the armature is 440 A. 570 A. 340 A. 250 A. 440 A. 570 A. 340 A. 250 A. ANSWER DOWNLOAD EXAMIANS APP
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