The armature torque of the D.C. shunt motor is proportional to____________?

Related Mcqs:

1. In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to

   A. 100% of the previous value
   B. 50% of the previous value
   C. 25% of the previous value
   D. 10% of the previous value
   E. none of the above

2. If a D.C. shunt motor is working at no load and if shunt field circuit suddenly opens__________?

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

3. 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

4. In a D.C. shunt motor, under the conditions of maximum power, the current in the armature will be_____________?

   A. almost negligible
   B. rated full-load current
   C. less than full-load current
   D. more than full-load current

5. If I2 be the armature current, then speed of a D.C. shunt motor is_______________?

   A. independent of Ia
   B. proportional to la
   C. varies as (Ia)
   D. varies as la

6. The current drawn by the armature of D.C. motor is directly proportional to__________?

   A. the torque required
   B. the speed of the motor
   C. the voltage across the terminals
   D. none of the above

7. If the field of a D.C. shunt motor gets opened while motor is running______________?

   A. the speed of motor will be reduced %
   B. the armature current will reduce
   C. the motor will attain dangerously high speed 1
   D. the motor will continue to nuvat constant speed

8. If the speed of a D.C. shunt motor is increased, the back e.m.f. of the motor will_________?

   A. increase
   B. decrease
   C. remain same
   D. become zero

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

   A. series motors
   B. shunt motors
   C. compound motors
   D. none of the above

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

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