electrical engineering Mcqs
1. economics of power generation2. analog electronics3. solid state switching circuits4. parallel circuits5. switchgear and protection6. op amp circuits7. transistor audio power amplifiers8. electrostatics9. heating and welding10. multi stage transistor amplifiers11. passive filters12. network theorems13. regulated d c power supply14. a c fundamentals circuits and circuit theory15. electromagnetic induction16. power electronics17. magnetism and electromagnetism18. transformers19. modulation and demodulation20. d c generators21. semiconductor theory22. single phase induction motors23. semiconductor diode24. hybrid parameters25. digital electronics26. oscillators27. earthing or grounding28. single stage transistor amplifiers29. d c motors30. transistor biasing31. amplifiers with negative feedback32. basic electrical33. electronic instruments34. synchronous motors35. field effect transistors fet36. magnetic circuit37. control systems38. industrial drives39. power generation40. series parallel circuits41. transistor tuned amplifiers42. electrical engineering materials43. rectifiers and converters44. integrated circuits45. scr silicon controlled rectifiers46. cables47. polyphase induction motors48. measurement and instrumentation49. transistors50. electrical machine design51. electrolysis and storage of batteries52. electric traction53. transmission and distribution
951. The wattage of motor for driving domestic sewing machine will be around__________?
comments icon0

A. 10 to 30 W

B. 40 to 75 W

C. 100 to 150 W

D. 5 to 10 W

952. Which of the following motors is inherently self starting ?
comments icon0
A. Shaded-pole motor

B. Split motor

C. None of these

D. Reluctance motor

953. The vafcie of transformation ratio of an induction motor can be found by__________?
comments icon0
A. short-circuit test only

B. stator resistance test

C. open-circuit test only

D. none of the above

954. The torque developed in the cage induction motor with autostarter is___________?
comments icon0
A. K2 x torque with direct switching

B. K x torque with direct switching

C. k/torque with direct switching

D. k2/torque with direct switching

955. The starting torque of a squirrel-cage induction motor is___________?
comments icon0

A. slightly more than full-load torque

B. low

C. negligible

D. same as full-load torque

956. In case of high speed universal motor which of the following needs more attention?
comments icon0

A. Air gap

B. Insulation in rotor

C. Balancing of rotor

D. End play

957. The synchronous motor is not inherently self-starting because_______________?
comments icon0

A. a rotating magnetic field does not have enough poles

B. the starting device to accelerate the rotor to near synchronous speed is absent

C. the force required to accelerate the rotor to the synchronous speed in an instant is absent

D. the rotating magnetic field is produced by only 50 Hz frequency currents

958. The speed regulation of a synchronous motor is always___________?
comments icon0

A. 1%

B. zero

C. positive

D. 0.50%

959. Synchronous motors are generally not self-starting because:
comments icon0

A. starting winding is not provided on the machines

B. startes cannot be used on these machines

C. the direction of instantaneous torque reverses after half cycle

D. the direction of rotation is not fixed

960. A reluctance motor____________?
comments icon0
A. all of the above

B. needs no D.C. excitation

C. is self-starting

D. is constant speed motor

961. For driving high inertia loads best type of induction motor suggested is_____________?
comments icon0
A. slip ring type

B. squirrel cage type

C. any of the above

D. none of the above

962. Which of the following motor will give the highest starting torque ?
comments icon0

A. D.C. shunt motor

B. Universal motor

C. Schrage motor

D. Repulsion start and induction run motor

963. Less maintenance troubles are experienced in case of___________?
comments icon0

A. slip ring induction motor

B. squirrel cage induction motor

C. both A. and (b)

D. none of the above

964. The speed/load characteristics of a universal motor is same as that of_____________?
comments icon0

A. none of the above

B. D.C. series motor

C. A.C. motor

D. D.C. shunt motor

965. In a three-phase induction motor_______________?
comments icon0
A. iron losses in stator will be more than that in rotor

B. iron losses in motor will be negligible as compared to that in rotor

C. iron losses in stator will be negligible as compared to that in rotor

D. iron losses in stator will be less than that in rotor

966. A double squirrel-cage induction motor has______________?
comments icon0
A. two parallel windings in rotor

B. two series windings in stator

C. two rotors moving in oppsite direction

D. two parallel windings in stator

967. Which of the following motor will have relatively higher power factor ?
comments icon0
A. Capacitor run motor

B. Shaded pole motor

C. Capacitor start motor

D. Split phase motor

968. A centrifugal switch is used to dis- connect starting winding when motor has___________?
comments icon0

A. run for about 5 minutes

B. picked up about 50 to 70 per cent of rated speed

C. run for about 1 minute

D. picked up about 10 to 25 per cent of rated speed

969. If in a synchronous motor, driving mechanical load and drawing current at lagging power factor from constant voltage supply, its field excitation is increased, then its power factor__________?
comments icon0

A. none of the above

B. remain constant

C. become less

D. become more

970. Which of the following motors is used in a situation where load increases with speed ?
comments icon0

A. Hysteresis motor

B. Induction motor

C. Three-phase series motor

D. Schrage motor

971. The starting winding of a single-phase motor is placed in_________?
comments icon0

A. armature

B. stator

C. field

D. rotor

972. Which of the following statements regarding two value capacitor motor is incorrect ?
comments icon0

A. It has low starting as well as rushing currents

B. It is a reversing motor

C. It has high starting torque

D. It is preferred to permanent-split single-value capacitor motor where frequent reversals are required
973. The ratio of starting torque to running torque in a synchronous motor is____________?
comments icon0

A. one

B. two

C. zero

D. infinity

974. If a particular application needs high speed and high starting torque, then which of the following motor will be preferred ?
comments icon0

A. Capacitor start motor

B. Shaded pole type motor

C. Capacitor start and run motor

D. Universal motor
975. The torque developed by a 3-phase induction motor least depends on__________?
comments icon0

A. rotor power factor

B. rotor current

C. shaft diameter

D. rotor e.m.f.

976. The rotor developed by a single-phase motor at starting is___________?
comments icon0
A. zero

B. less than the rated torque

C. more than i.he rated torque

D. rated torque

977. In three-phase squirrel-cage induction motors____________?
comments icon0
A. rotor conductors are short-circuited through end rings

B. rotor conductors are kept open

C. rotor conductor ends are short-circuited through slip rings

D. rotor conductors are connected to insulation

978. In an induction motor if air-gap is increased__________?
comments icon0

A. bearing friction will reduce

B. the power factor will be low

C. windage losses will be more

D. copper loss will reduce In an induction motor

979. The repulsion-start induction-run motor is used because of___________?
comments icon0
A. high starting torque

B. good power factor

C. minimum cost

D. high efficiency

980. Armature of a synchronous machine is____________?
comments icon0

A. of reducing number of slip rings on the rotor

B. armature is associated with large power as compared to the field circuits

C. all of the above reasons

D. of difficulty of providing high voltage insulation on rotor

981. Slip-rings in a synchronous motor carry____________?
comments icon0

A. alternating current

B. no current

C. all of the above

D. direct current
982. The power factor of an induction motor under no-load conditions will be closer to_____________?
comments icon0

A. unity

B. 0.2 lagging

C. 0.5 leading

D. 0.2 leading

983. The direction of rotation of universal motor can be reversed the by reversing the flow of current through__________?
comments icon0

A. armature winding

B. none of the above

C. field winding

D. either armature winding or field winding
984. The term cogging is associated with___________?
comments icon0
A. induction motors

B. compound generators

C. three phase transformers

D. D.C. series motors

985. In a squirrel cage motor the induced e.m.f. is___________?
comments icon0

A. none of the above

B. dependent on the shaft loading

C. slip times the stand still e.m.f. induced in the rotor

D. dependent on the number of slots

986. The standard full-load power factor ratings for synchronous motors are___________?
comments icon0

A. unity or zero

B. unity or 0.8 leading

C. zero or 0.8 leading

D. unity or 0.8 lagging

987. Temperature of the stator winding of a three phase induction motor is obtained by___________?
comments icon0

A. embedded temperature method

B. resistance rise method

C. thermometer method

D. all above methods
988. Which of the following motors can be run on AC. as well as D.C. supply ?
comments icon0

A. Reluctance motor

B. Universal motor

C. Repulsion motor

D. Synchronous motor

989. In a hysteresis motor, the rotor must have____________?
comments icon0

A. susceptibility

B. retentivity

C. resistivity

D. none of the above

990. In case one phase of a three-phase synchronous motor is short-circuited the motor will____________?
comments icon0

A. run with excessive vibrations

B. take less than the rated load

C. not start

D. run at 2/3 of synchronous speed

991. A 3-phase 440 V, 50 Hz induction motor has 4% slip. The frequency of rotor e.m.f. will be____________?
comments icon0

A. 200 Hz

B. 50 Hz

C. 0.2 Hz

D. 2 Hz
992. An induction motor can run at synchronous speed when____________?
comments icon0

A. it is run on voltage higher than the rated voltage

B. e.m.f. is injected in the rotor circuit

C. it is run on load

D. it is run in reverse direction

993. The rotor of an induction motor runs at__________?
comments icon0

A. above synchronous speed

B. below synchronous speed

C. synchronous speed

D. any of the above

994. The low power factor of induction motor is due to___________?
comments icon0
A. all of the above

B. stator reactance

C. the reactive lagging magnetizing current necessary to generate the magnetic flux

D. rotor leakage reactance

995. In case of the induction motors the torque is___________?
comments icon0

A. directly proportional to (slip)2

B. inversely proportional to (Vslip)

C. inversely proportional to slip

D. directly proportional to slip
996. In a star-delta starter of an induction motor___________?
comments icon0

A. resistance is inserted in the rotor

B. reduced voltage is applied to the stator

C. applied voltage perl stator phase is 57.7% of the line voltage

D. resistance is inserted in the stator

997. The induced e.m.f. in a synchronous motor working on leading power factor will be_____________?
comments icon0

A. equal to the supply voltage

B. less than the supply voltage

C. more than the supply voltage

D. None of these

998. In which single-phase motor, the rotor has no teeth or winding ?
comments icon0

A. Universal motor

B. Reluctance motor

C. Split phase motor

D. Hysteresis motor
999. A single-phase induction motor is__________?
comments icon0

A. inherently non-self-starting with high torque

B. inherently self-starting with low torque

C. inherently self-starting with high torque

D. inherently non-self-starting with low torque
1000. A repulsion motor is equipped with__________?
comments icon0

A. slip rings

B. commutator

C. both A. and (b)

D. none of the above