Electrical Machines The frequency of voltage generated by an alternator having 8 poles and rotating at 250 rpm is 25 Hz. 50 Hz. 16.67 Hz. 60 Hz. 25 Hz. 50 Hz. 16.67 Hz. 60 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an additional resistance is connected in series with a DC motor operating at rated speed, the speed of the motor will Remain unaltered. Oscillate around the normal speed. Increase. Reduce. Remain unaltered. Oscillate around the normal speed. Increase. Reduce. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The flux involved in the emf equation of a transformer has maximum value. average value. total value. rms value. maximum value. average value. total value. rms value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The result of slip test on a 3-phase, 20 KVA, 400 V, 50 Hz connected salient pole alternator is given below- Phase value: Vmax = 100 V, Vmin = 96 V, Imax = 10 A and I min = 7 A. The direct and quadranature axis reactances are respectively 8.248 and 5.54 Ω. 14.28 and 9.60 Ω. 14.28 and 5.54 Ω. 8.248 and 9.60 Ω. 8.248 and 5.54 Ω. 14.28 and 9.60 Ω. 14.28 and 5.54 Ω. 8.248 and 9.60 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Conservator tank is used None of these to act as an oil storage. to take up the expansion of oil due to temperature rise. for better cooling of transformer. None of these to act as an oil storage. to take up the expansion of oil due to temperature rise. for better cooling of transformer. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Lamination of transformer core is made of wrought iron. cast iron. silicon steel. cast steel. wrought iron. cast iron. silicon steel. cast steel. ANSWER DOWNLOAD EXAMIANS APP
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