Electrical Machines
Armature reaction in a DC machine

 is in the same direction as the main poles.
  makes an angle of 90° with the main pole axis.
 is in direct opposition to the main poles.
 makes an angle with the main pole axis which is load dependent.

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Electrical Machines
In a DC machine, for the same value of φ, Z and N; which one of the following statements is correct?

  Armature emf is more with wave winding than with lap winding.
 Armature emf is less with wave winding than with lap winding.
 Armature emf depends on weather the machine is running as a motor or generator.
 Armature emf is same as long as the flux density in the air gap remains the same.

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Electrical Machines
Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are identical as 4% from no load to full load. Consider the governors operating at 50Hz on no load. How will the machine share, if the load is 600 MW?

 230.7 MW and 369.23 MW respectively
 generator 2 gets over load
 generator 1 gets over load
 200 MW and 400MW respectively

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