Electrical Machines How can the synchronous speed of a 3 - Φ IM be varied? By varying the supply frequency. Both (A) and (B). By varying number of poles. By varying supply voltage. By varying the supply frequency. Both (A) and (B). By varying number of poles. By varying supply voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole DC shunt generator having a wave winding supplies 50 lamps, each of 60 W at 120 V. The armature and field resistance are 0.2 Ω and 60 Ω respectively. The current in each armature conductor is 13.5 A. 11.5 A. 27 A. 23 A. 13.5 A. 11.5 A. 27 A. 23 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An alternator is feeding an infinite busbar. Its prime mover is suddenly shutdown. The alternator will continue to work as synchronous motor with same direction of rotation. come to stand still. start working as induction motor. continue to work as alternator but the direction of rotation will reverse. continue to work as synchronous motor with same direction of rotation. come to stand still. start working as induction motor. continue to work as alternator but the direction of rotation will reverse. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC shunt generator working on load, the brushes are moved forward in the direction of rotation, as a result of this, commutation will improve and terminal voltage will rise . improve but terminal voltage will fall. worsen and terminal voltage will fall worsen and terminal voltage will rise. improve and terminal voltage will rise . improve but terminal voltage will fall. worsen and terminal voltage will fall worsen and terminal voltage will rise. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Capacitor start capacitor run provides high staring torque and high power factor. none. high staring torque only. high power factor only. high staring torque and high power factor. none. high staring torque only. high power factor only. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The mechanical power is developed by a DC motor is maximum when none of above. back emf is equal to half of applied voltage. back emf is equal to twice of applied voltage. back emf is equal to applied voltage. none of above. back emf is equal to half of applied voltage. back emf is equal to twice of applied voltage. back emf is equal to applied voltage. ANSWER DOWNLOAD EXAMIANS APP