Electrical Machines Flashing of DC generator means None of these increasing flux density by providing extra ampere-turns in field. creation of residual magnetism by a DC source. neutralization of residual magnetism. None of these increasing flux density by providing extra ampere-turns in field. creation of residual magnetism by a DC source. neutralization of residual magnetism. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 3, 4, 5 2, 3, 6 2, 4, 5, 6 1, 2, 5 3, 4, 5 2, 3, 6 2, 4, 5, 6 1, 2, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt generator builds up to a voltage of 220 V at no load while running at its rated speed. If the speed of the generator is raised by 25% kepping the circuit conditions unaltered, then the Voltage to which the machine would build up will increase to a value greater than 1.25 times 220 V not change and remain at 220 V increase to 1.25 times 220 V increase to value lying between 220 V and 1.25 times 220 V increase to a value greater than 1.25 times 220 V not change and remain at 220 V increase to 1.25 times 220 V increase to value lying between 220 V and 1.25 times 220 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Use of fractional pitch winding All of these make it stiffer. results in reduced axial length of the machine. results in reduced leakage reactance. All of these make it stiffer. results in reduced axial length of the machine. results in reduced leakage reactance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Capacitor start capacitor run provides high staring torque only. high power factor only. none. high staring torque and high power factor. high staring torque only. high power factor only. none. high staring torque and high power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A series motor is efficiently suitable for none of these. constant speed operation. high starting torque operation. low starting torque operation. none of these. constant speed operation. high starting torque operation. low starting torque operation. ANSWER DOWNLOAD EXAMIANS APP