A. Torque and speed are inversely proportional to armature current
B. Torque is proportional to armature current
C. Torque is proportional to square root of armature current
D. The speed is inversely proportional to the torque and the torque is proportional to square of armature current
Related Mcqs:
- Differentially compound D.C. motors can find applications requiring___________?
A. high starting torque
B. low starting torque
C. variable speed
D. frequent on-off cycles - For which of the following applications a D.C. motor is preferred over an A.C. motor ?
A. Low speed operation
B. High speed operation
C. Variable speed operation
D. Fixed speed operation - In which of the following applications D.C. series motor is invariably tried?
A. Starter for a car
B. Drive for a water pump
C. Fan motor
D. Motor operation in A.C. or D.C - Starters are used with D.C. motors because______________?
A. these motors have high starting torque
B. these motors are not self-starting
C. back e.m.f. of these motors is zero initially
D. to restrict armature current as there is no back e.m.f. while starting - In case of D.C. shunt motors the speed is dependent on back e.m.f. only because____________?
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 - In case of conductively compensated D.C. series motors, the compensating winding is provided______________?
A. as separately wound unit
B. in parallel with armature winding
C. in series with armature winding
D. in parallel with field winding - Which of the following motors one will choose to drive the rotary compressor ?
A. D.C. shunt motor
B. D.C. series motor
C. Universal motor
D. Synchronous motor - Which of the following motors is usually used in house-hold refrigerators ?
A. D.C. shunt motor
B. D.C. series motor
C. Single phase induction motor (split phase start or induction run motor)
D. Reluctance motor
E. Synchronous motor - D.C. shunt motors are used for driving____________?
A. trains
B. cranes
C. hoists
D. machine tools - 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
