Electrical Machines
A smaller air gap in a induction motor helps to

 increase the starting torque.
 reduce the chance of cogging.
 reduce the magnetizing current.
 reduce the chance of crawling.

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Electrical Machines
In a DC generator, the armature reaction results in

 magnetization of leading and demagnetization of trailing pole tip.
  magnetization of inter poles.
  demagnetization of leading & magnetization of trailing pole tip.
 demagnetization of centers of poles.

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Electrical Machines
A dc shunt generator, when driven without any excitation, showed an open circuit voltage of 12 V. When the field winding was excited, the voltage dropped to zero. It happened because

 there was a break in the armature circuit
 there was no residual magnetism in the field circuit
 field winding was wrongly connected
 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 5.54 Ω.
 14.28 and 9.60 Ω.
 8.248 and 5.54 Ω.
 8.248 and 9.60 Ω.

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