A. back e.m.f. is equal to armature drop
B. armature drop is negligible
C. flux is proportional to armature current
D. flux is practically constant in D:C. shunt motors
Related Mcqs:
- 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 - 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 - 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 - 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 - In D.C. shunt motors as load is reduced__________________?
A. the speed will increase abruptly
B. the speed will increase in proportion to reduction in load
C. the speed will remain almost/constant
D. the speed will reduce - D.C. shunt motors are used for driving____________?
A. trains
B. cranes
C. hoists
D. machine tools - As -the load is increased the speed of D.C. shunt motor will____________?
A. reduce slightly
B. increase slightly
C. increase proportionately
D. remains unchanged - The speed of a D.C. shunt motor can be increased by_______________?
A. increasing the resistance in armature circuit
B. increasing the resistance in field circuit
C. reducing the resistance in the field circuit
D. reducing the resistance in the armature circuit - If the load on a DC shunt motor is increases, its speed is slightly reduced due to______________?
A. increase in armature current
B. increase in flux
C. decrease in reactance
D. decrease in back emf - Which of the following method is used for the speed control of DC shunt motor?
A. voltage control method
B. flux control method
C. rheostat control method
D. all of the above
