Electrical Machines In DC motors, under trailing pole tips, flux density will_______ ? None of these either increase or decrease increase decrease None of these either increase or decrease increase decrease ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following DC Motor uses 4-point starter? DC shunt motor with armature resistance. DC shunt motor with field weaking control. DC compound motor. DC series motor. DC shunt motor with armature resistance. DC shunt motor with field weaking control. DC compound motor. DC series motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 2, 4 1, 3 1, 4 2, 3 2, 4 1, 3 1, 4 2, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An alternator is feeding an infinite busbar. Its prime mover is suddenly shutdown. The alternator will come to stand still. continue to work as alternator but the direction of rotation will reverse. continue to work as synchronous motor with same direction of rotation. start working as induction motor. come to stand still. continue to work as alternator but the direction of rotation will reverse. continue to work as synchronous motor with same direction of rotation. start working as induction motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the supply terminal of a DC shunt motor are interchanged The motor will stop. The motor will run much faster in the same direction. The motor will run at its normal speed in the same direction as before. The direction of rotation will reverse. The motor will stop. The motor will run much faster in the same direction. The motor will run at its normal speed in the same direction as before. The direction of rotation will reverse. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2A armature current at no-load, when the armature current is changed to 20A at loaded condition the speed is 1000 r.p.m. What is the speed at no-load? 4575.4 r.p.m. 963.8 r.p.m. 1130 r.p.m. 1037.5 r.p.m. 4575.4 r.p.m. 963.8 r.p.m. 1130 r.p.m. 1037.5 r.p.m. ANSWER DOWNLOAD EXAMIANS APP