Electrical Machines In a transformer maximum flux density is not constant, the eddy current loss varies as V f² V² f V f² V² f ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous generator is feeding a zero power factor (lagging) load at rated current. The armature reaction is cross – magnetizing. ineffective. demagnetizing. magnetizing. cross – magnetizing. ineffective. demagnetizing. magnetizing. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Motors for fans and pumps are selected in the rpm range 500 to 720. 375 to 500. 1440 to 2880. 720 to 920. 500 to 720. 375 to 500. 1440 to 2880. 720 to 920. 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, 4 ,5 1, 3, 5 2, 3 , 5 1, 4 2, 4 ,5 1, 3, 5 2, 3 , 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a transformer is loaded, the secondary terminal voltage drops. That means power factor is zero. unity. lagging. leading. zero. unity. lagging. leading. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines 1 KVA, 230 V, 50 Hz, single phase transformer has an eddy current loss of 30 watts. The eddy current loss when the transformer is excited by a dc source of same voltage will be zero watt less than 30 W 30 W more than 30 W zero watt less than 30 W 30 W more than 30 W ANSWER DOWNLOAD EXAMIANS APP
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