Electrical Machines
If the excitation is critical, the power factor of the alternator is

None of these
 leading power factor.
 unity power factor.
 lagging power factor.

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Electrical Machines
A dc shunt generator, when commissioned after a major repair of the field system, failed to build Up voltage. It was because

 field winding was wrongly connected
 there was a break in the armature circuit
 field system lost residual magnetism
 field resistance was higher than critical resistance

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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

 14.28 and 9.60 Ω.
 8.248 and 9.60 Ω.
  14.28 and 5.54 Ω.
 8.248 and 5.54 Ω.

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