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
3951. Overload relays are of_______________type
comments icon0

A. electromagnetic

B. all above

C. solid state

D. induction

E. thermal

3952. The current zero interruption, in oil and air blast circuit breakers, is achieved by_______________?
comments icon0

A. lengthening of the gap

B. cooling and blast effect

C. both A. and B

D. deionizing the oil with forced air

E. none of the above

3953. SF6 gas______________?
comments icon0

A. none of the above

B. is lighter than air

C. is yellow in colour

D. is nontoxic

E. has pungent small

3954. H.R.C. fuse, as compared to a rewirable fuse, has_________________?
comments icon0

A. high speed of operation

B. all of the above

C. no ageing effect

D. high rupturing capacity

3955. Directional relays are based on flow of____________?
comments icon0

A. voltage wave

B. all of the above

C. current

D. power
3956. A switchgear is device used for_____________?
comments icon0

A. switching an electrical circuit 111.

B. interrupting an electrical circuit

C. switching and controlling an electrical circuit

D. switching, controlling and protecting the electrical circuit and equipment
3957. The relay operating speed depends upon_________________?
comments icon0
A. all of the above

B. armature core air gap

C. the spring tension

D. the rate of flux built up

3958. Protective relays are devices that detect abnormal conditions in electrical circuits by measuring_____________?
comments icon0

A. none of the above

B. voltage during abnormal condition

C. constantly the electrical quantities which differ during normal and abnormal conditions

D. current during abnormal condition

3959. Series reactors should have________________?
comments icon0

A. high impedance

B. low resistance

C. low impedance

D. high resistance

3960. The contacts of high voltage switches used in power system are submerged in oil. The main purpose of the oil is to______________?
comments icon0

A. none of the above

B. lubricate the contacts

C. extinguish the arc

D. insulate the contacts from switch body

E. all of the above

3961. A fuse is connected_______________?
comments icon0

A. in parallel with circuit

B. none of the above

C. either in series or in parallel with circuit

D. in series with circuit
3962. A short-circuit is identified by_____________?
comments icon0
A. heavy current flow

B. no current flow

C. voltage drop

D. voltage rise

3963. Thermal circuit breaker has____________?
comments icon0
A. delayed trip action

B. instantaneous trip action

C. both of the above

D. none of the above

3964. H.R.C. fuses provide best protection against________________?
comments icon0

A. overload

B. reverse current

C. short-circuits

D. open-circuits

3965. Bus coupler is very essential in arrangement______________?
comments icon0
A. main and transfer bus

B. all of the above

C. double bus, double breaker

D. single bus

3966. Thermal overload relays are used to protect the motor against over current due to____________?
comments icon0

A. grounds

B. heavy loads

C. all of the above

D. short-circuits

3967. For cost and safety, the outdoor substations are installed for voltages above_________________?
comments icon0
A. 33 kV

B. 110kV

C. 60kV

D. 11 kV

3968. The steady state stability of the power system can be increased by_____________?
comments icon0

A. none of the above

B. connecting lines in series

C. connecting lines in parallel

D. using machines of high impedance

E. reducing the excitation of machines

3969. Oil switches are employed for_____________?
comments icon0

A. low currents circuits

B. all circuits

C. low voltages circuits

D. high voltages and large currents circuits
3970. Protection by fuses is generally not used beyond__________?
comments icon0

A. 20 A

B. 100 A

C. 50 A

D. 200 A

3971. The reflection co-efficient at the open circuited end of a transmission line___________?
comments icon0

A. infinity

B. none of the above

C. zero

D. unity
3972. Insulation resistance of high voltage circuit breakers is more than________________?
comments icon0
A. 100 mega ohms

B. 500 mega ohms

C. 1 mega ohms

D. 10 mega ohms

3973. Which of the following statements is incorrect ?
comments icon0
A. Lightning arrestors are used before the switchgear

B. The peak short current is (1.8 xV2) times the A.C. component

C. Shunt reactors are used as compensation reactors

D. The MVA at fault is equal to base MVA divided by per unit equivalent fault reactance

3974. The short circuit in any winding of the transformer is the result of______________?
comments icon0

A. mechanical vibration

B. loose connection

C. impulse voltage

D. insulation failure

3975. The inductive interference between power and communication line can be minimized by__________?
comments icon0

A. transposition of the power line

B. transposition of the communication line

C. both (A) and (B)

D. increasing the distance between the conductors

3976. For which of the following ratings of the transformer differential protection is recommended ?
comments icon0

A. none of the above

B. above 30 kVA.

C. equal to and above 5 MVA

D. equal to and above 25 MVA

3977. Which of the following circuit breakers has high reliability and minimum maintenance ?
comments icon0

A. Vacuum circuit breakers

B. Air blast circuit breakers

C. Circuit breaker with SF6 gas

D. Oil circuit breakers

3978. A.C. network analyser is used to solve problems of_______________?
comments icon0
A. load flow, short-circuit and stability

B. none of the above

C. load flow

D. load flow and short-circuit

E. load flow and stability

3979. To reduce short circuit fault currents are used_____________?
comments icon0

A. none of the above

B. capacitors

C. resistors

D. reactors
3980. Which of the following devices will receive voltage surge first travelling on the transmission line ?
comments icon0

A. Relays

B. Switchgear

C. Step-down transformer

D. Lightning arresters
3981. Induction cup relay is operated due to changes in________________?
comments icon0

A. impedance

B. voltage

C. current

D. all of the above
3982. Distance relays are generally_____________?
comments icon0

A. split-phase relays

B. none of the above

C. reactance relays

D. impedance relays

3983. The short circuit in any winding of the transformer is the result of_______________?
comments icon0

A. loose connection

B. mechanical vibration

C. insulation failure

D. impulse voltage
3984. Arc in a circuit behaves as_______________?
comments icon0
A. a resistance decreasing with voltage rise across the arc

B. a resistance increasing with voltage rise across the arc

C. an inductive reactance

D. a capackive reactance

3985. On which of the following routine tests are conducted ?
comments icon0
A. All of the above

B. Oil circuit breakers

C. Air blast circuit breakers

D. Minimum oil circuit breakers

3986. Circuit breakers usually operate under______________?
comments icon0

A. sub-transient state of short-circuit current

B. after D.C. component has ceased

C. steady state of short-circuit current

D. transient state of short-circuit current
3987. Circuit breakers are essentially____________?
comments icon0

A. circuits to break the system

B. current carrying contacts called electrodes

C. any of the above

D. transformers to isolate the two systems

E. arc extinguishers

3988. Short-circuit currents are due to_______________?
comments icon0

A. three phase faults

B. single phase to ground faults

C. two phase to ground faults

D. phase to phase faults

E. any of these
3989. The information to the circuit breaker under fault conditions is provided by____________?
comments icon0

A. all of the above

B. relay

C. rewirable fuse

D. H.R.C. only

3990. The delay fuses are used for the protection of ___________?
comments icon0

A. fluorescent lamps

B. motors

C. light circuits

D. power outlet circuits

3991. A fuse in a motor circuit provides protection against__________?
comments icon0

A. overload

B. open circuit, short-circuit and overload

C. none of the above

D. short-circuit and overload
3992. Over voltage protection is recommended for______________?
comments icon0

A. none of the above

B. all of the above

C. gas turbine generators

D. steam turbine generators

E. hydro-electric generators

3993. Air blast circuit breaker is used for_____________?
comments icon0

A. over currents

B. short duty

C. intermittant duty

D. repeated duty
3994. The fuse rating is expressed in terms of_____________?
comments icon0

A. voltage

B. kVA

C. VAR

D. current
3995. relay is preferred for phase fault on short transmission line?
comments icon0
A. Reactance

B. None of the above

C. Induction type

D. Impedance

3996. relays are used for phase faults on long line?
comments icon0

A. Reactance

B. Impedance

C. None of the above

D. Either of the above

3997. A balanced 3-phase system consists of_______________?
comments icon0

A. zero, negative and positive sequence currents

B. zero sequence currents only

C. positive sequence currents only

D. negative and zero sequence currents

3998. Overfluxing protection is recommended for_____________?
comments icon0
A. generator transformer of the power plant

B. station transformer of the power plant

C. distribution transformer

D. auto-transformer of the power plant

3999. A fuse is never inserted in____________?
comments icon0

A. phase dine

B. neutral wire

C. positive of D.C. circuit

D. negative of D.C. circuit

4000. Interruption of large currents by relay requires______________?
comments icon0

A. wide separation of the opened contacts

B. all of the above

C. high speed opening of contacts

D. arc suppressing blow out coils