The ratio of starting torque to full-load torque is least in case of____________?

Related Mcqs:

1. Which of the following load normally needs starting torque more than the rated torque?

   A. Blowers
   B. Conveyors
   C. Air compressors
   D. Centrifugal pumps

2. For the same H.P. rating and full load speed, following motor has poor starting torque_____________?

   A. shunt
   B. series
   C. differentially compounded
   D. cumulativelyc’ompounded

3. Which of the following application requires high starting torque ?

   A. Lathe machine
   B. Centrifugal pump
   C. Locomotive
   D. Air blower

4. Following motor is used where high starting torque and wide speed range control is required?

   A. Single phase capacitor start
   B. Induction motor
   C. Synchronous motor
   D. D.C. motor
   E. None of the above

5. Buses, trains, trolleys, hoists, cranes require high starting torque and therefore make use of_____________?

   A. D.C. series motor
   B. D.C. shunt motor
   C. induction motor
   D. all of above motors

6. The speed of a D.C. shunt motor more than its full-load speed can be obtained by_____________?

   A. decreasing the field current
   B. increasing the field current
   C. decreasing the armature current
   D. increasing the armature current

7. If a D.C. shunt motor is working at full load and if shunt field circuit suddenly opens____________?

   A. this will make armature to take heavy current, possibly burning it
   B. this will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses
   C. nothing will happen to motor
   D. motor will come to stop

8. The speed of a D.C. shunt motor is required to be more than full load speed. This is possible by______________?

   A. reducing the field current
   B. decreasing the armature current
   C. increasing the armature current
   D. increasing the excitation current
   E. none of the above methods

9. Usually wide and sensitive speed control is desired in case of____________?

   A. centrifugal pumps
   B. elevators
   C. steel rolling mills
   D. colliery winders

10. D.C. motor is to a drive a load which is almost nil for certain part of the load cycle and peak value for short duration. We will select this______________?

    A. series motor
    B. shunt motor
    C. compound motor
    D. any of the above