0 Comment

Practice Test: Question Set - 04

1. Insertion of reactance in the rotor circuit
    (A) Reduces starting torque as well as maximum torque
    (B) Increases starting torque as well as maximum torque
    (C) Increases starting torque but maximum torque remains unchanged
    (D) Increases starting torque but maximum torque decreases

2. Slip ring motor is preferred over squirrel cage induction motor where
    (A) High starting torque is required
    (B) Load torque is heavy
    (C) Heavy pull out torque is required
    (D) All of the above

3. In squirrel cage induction motors, the rotor slots are usually given slight skew in order to
    (A) Reduce windage losses
    (B) Reduce eddy currents
    (C) Reduce accumulation of dirt and dust
    (D) Reduce magnetic hum

4. The good power factor of an induction motor can be achieved if the average flux density in the air gap is
    (A) Absent
    (B) Small
    (C) Large
    (D) Infinity

5. For which motor the speed can be controlled from rotor side?
    (A) Squirrel-cage induction motor
    (B) Slip-ring induction motor
    (C) Both (A) and (B)
    (D) None of the above

6. Size of a high speed motor as compared to low speed motor for the same H.P. will be
    (A) Bigger
    (B) Smaller
    (C) Same
    (D) Any of the above

7. The speed characteristics of an induction motor closely resemble the speed-load characteristics of which of the following machines
    (A) D.C. series motor
    (B) D.C. shunt motor
    (C) Universal motor
    (D) None of the above

8. The vafcie of transformation ratio of an induction motor can be found by
    (A) Open-circuit test only
    (B) Short-circuit test only
    (C) Stator resistance test
    (D) None of the above

9. The circle diagram for an induction motor cannot be used to determine
    (A) Efficiency
    (B) Power factor
    (C) Frequency
    (D) Output

10. Temperature of the stator winding of a three phase induction motor is obtained by
    (A) Resistance rise method
    (B) Thermometer method
    (C) Embedded temperature method
    (D) All above methods

Show and hide multiple DIV using JavaScript View All Answers

Post a Comment Blogger