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 23 A. 11.5 A. 27 A. 13.5 A. 23 A. 11.5 A. 27 A. 13.5 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ideal value of voltage regulation of a device is? ∞ a positive finite value 0 a finite negative value ∞ a positive finite value 0 a finite negative value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An ideal synchronous motor has no starting torque because rotor is made up of salient poles. relative velocity between the stator and rotor mmf’s is zero. rotor winding is highly reactive. relative velocity between stator and rotor mmf’s is not zero. rotor is made up of salient poles. relative velocity between the stator and rotor mmf’s is zero. rotor winding is highly reactive. relative velocity between stator and rotor mmf’s is not zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 1, 4 2, 3 , 5 1, 3, 5 2, 4 ,5 1, 4 2, 3 , 5 1, 3, 5 2, 4 ,5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following methods of speed control is not affected through stator side? Change of number of pole. Change of rotor resistance. Change of supply voltage. Change of supply frequency. Change of number of pole. Change of rotor resistance. Change of supply voltage. Change of supply frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole dynamo with wave wound armature has 51 slots contains 20 conductors in each slot. If induced emf 357 Volts and speed is 8500 rpm, flux per pole will be 1.2 mWb. 1.4 mWb. 3.5 mWb. 2.7 mWb. 1.2 mWb. 1.4 mWb. 3.5 mWb. 2.7 mWb. ANSWER DOWNLOAD EXAMIANS APP