A. 4.0
B. 2.0
C. 1.0
D. 0.5
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
In variable speed motor___________?
A. a stronger commutating field is needed at low speed than at high speed
B. a weaker commutating field is needed at low speed than at high speed
C. same commutating field is needed at low speed than at high speed
D. none of the above is correct
Which of the following tests will be suitable for testing two similar D.C. series motors of large capacity ?
A. Swinburne’s test
B. Hopkinson’s test
C. Field test
D. Brake test
In a D.C. generator all of the following could be the effects of iron losses except___________?
A. Loss of efficiency
B. Excessive heating of core
C. Increase in terminal voltage
D. Rise in temperature of ventilating air
If a D.C. motor is to be selected for conveyors, which rriotor would be preferred ?
A. Series motor
B. Shunt motor
C. Differentially compound motor
D. Cumulative compound motor
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