Electric Drives Practice Test 2

1. The ferrite cores are used for ____________ transformers.

2. Calculate the phase angle of the sinusoidal waveform z(t)=78sin(456πt+2π÷78).

3. Calculate the active power in a 5 Ω resistor with 5 A current flowing through it.

4. A three-phase slip ring induction motor is fed from the rotor side with the stator winding short-circuited. The frequency of the current flowing in the short-circuited stator is ____________

5. What is the unit of the admittance?

6. 340 V, 45 A, 1400 rpm DC separately excited motor having a resistance of .7 ohm excited by an external dc voltage source of 90 V. Calculate the torque developed by the motor on full load.

7. A 2-pole lap wound generator with 44 armature conductors and a flux per pole of .07 Wb has an armature current of 80 A. The developed torque is _________

8. The generated e.m.f from 16-pole armature having 57 turns driven at 78 rev/sec having flux per pole as 5 mWb, with lap winding is ___________

9. Calculate the radius of the circular ring having a moment of inertia 59 kgm² and mass of 69 kg.

10. Calculate the moment of inertia of the thin spherical shell having a mass of 3 kg and diameter of 66 cm.