Electrical Machines Which of the following load normally needs starting torque more than rated torque?

Conveyers.
Centrifugal pumps.
Blowers.
Air compressors.

Electrical Machines In a DC generator if field winding attains the critical resistance

machine will generate maximum voltage.
field winding will burn.
the voltage generated will be zero.
machine will generate maximum power.

Electrical Machines When pure inductive load is connected to the alternator, what is the effect of armature reaction?

Demagnetization
Cross magnetization
Magnetization
None of these

Electrical Machines A three phase 400 V, 6 pole, 50 Hz, squirrel cage induction motor is running at a slip of 5%. The speed of stator magnetic field with respect to rotor magnetic field and speed of rotor w.r.t stator magnetic field are

zero , - 50 rpm.
1000 rpm, 950 rpm.
zero, 950 rpm.
1000 rpm, - 50 rpm.

Electrical Machines In a 3 - ÃŽÂ¦ IM with line frequency f1 and winding factor kw1 and kw2 for stator and rotor respectively the ratio of per phase stator winding emf E1 to per phase rotor winding emf E2 at standstill is given by

E1 / E2 = N1 / N2.
E1 / E2 = N1kw1 / N2kw2.
E1 / E2 = f1kw1 / f2kw2.
E1 / E2 = 1.

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

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