ELECTRICAL & ELECTRONICS ENGINEERING PRACTICE QUESTIONS

1. Ohm’s law applicable for

(a) linear circuits only

(b) non linear circuits only

(c) both linear and non linear circuits

(d) none of these

Ans: a
2. Unit of current is

(a) Ampere

(b) Volt

(c) Watt

(d) Volt-ampere
Ans: a
3. What is the equivalent resistance when 10 Ohms and 20 Ohms resistors are connected

in series

(a) 35 Ohms

(b) 25 Ohms

(c) 30Ohms

(d) none of these
Ans: c
4. Form factor is defined as the ratio of

(a) Average value to Maximum value

(b) Maximum value to Average value

(c) Peak value to R.M.S Value

(d) R.M.S Value to Average value
Ans: d
5. R.M.S Value of full wave rectified sinusoidal voltage is

(a) V_M/3

(b) V_M/2

(c) V_M/Ö2

(d) none of these
Ans: c
6. Power factor for resistive load is

(a) Zero

(b) Unity

(c) Infinity

(d) 0.2
Ans: b
7. voltage is a ——quantity

(a) Scalar

(b) Vector

(c) Scalar and Vector

(d) none of these
Ans: b
8. In D.C , Capacitor acts as

(a) Short circuit

(b) Open circuit

(c) either (a)or (b)

(d) none of these
Ans: b
9 In 3 phase star circuit, phase voltage is

(a) V_Ph =Ö3 V_L

(b) V_Ph = V_L /Ö3

(c) V_Ph = V_L

(d) V_Ph =3 V_L
Ans: b
10. In 3 phase delta circuit, line current is

(a) I_L =I _Ph

(b) I_L =2 I _Ph

(c) I_L =3 I _Ph

(d) I_L =Ö3 I _Ph
Ans:d
11. What is the equivalent resistance when 20Ohms and 20Ohms resistors are

connected in parallel

(a) 45 Ohms

(b) 10Ohms

(c) 54 Ohms

(d) 30Ohms
Ans: b
12. Voltage-Current relationship in resistor element is

(a) In phase

(b) Out of phase

(c) No Relation

(d) constant
Ans:a

13. For high voltage applications which type of 3 phase circuit to be Preferred

(a) Star

(b) Delta

(c) Star or Delta

(d) Neither Star nor Delta
Ans: b
14. What is the unit of Reactive Power

(a) KVA

(b) KW

(c) HP

(d) KVAR
Ans:d
15. R.M.S Value of Half wave rectified sinusoidal voltage is

(a) V_M/3

(b) V_M/2

(c) V_M/Ö2

(d) none of these
Ans: b
16. Current is defined as

(a) Charge/time

(b) Time/charge

(c) power/time

(d) None of these
Ans:a
17. Active elements are

(a) Voltage sources only

(b) Current sources only

(c) Resistors only

(d) Both Voltage and Current sources
Ans: d

18. In Bilateral Network the current flows in

(a) Unidirectional

(b) Bidirectional

(c) Rotational

(d) None of these
Ans: b

19. D.C has

(a) Constant magnitude

(b) Variable magnitude

(c) Fixed Polarities

(d) Constant magnitude and Fixed Polarities
Ans: d

20. In Capacitive circuit, Current flows in the capacitor

(a) i=C (dv/dt)

(b) i=V(dc/dt)

(c) i=C(di/dt)

(d) i=Ct
Ans: a

21. Unit of voltage is

(a) Ampere

(b) Volt

(c) Watt

(d) Volt-ampere
Ans: b

22. Peak factor is defined as the ratio of

(a) Average value to Maximum value

(b) Maximum value to Average value

(c) Peak value to R.M.S Value

(d) R.M.S Value to Average value
Ans: c
23. Average value is

(a) area/period

(b) period/area

(c) length/area

(d) none of these
Ans: a
24. Unit of power is

(a) Ampere

(b) Volt

(c) Watt

(d) joules
Ans:c
25. Unit of apparent power is

(a) Ampere

(b) Volt

(c) Watt

(d) Volt-ampere
Ans:d
26. Unit of energy is

(a) KWH

(b) Volt

(c) Watt

(d) Volt-ampere
Ans:a
27. A.C has

(a) Constant magnitude

(b) Variable magnitude

(c) Fixed Polarities

(d) Constant magnitude and Fixed Polarities
Ans: b

28. Passive elements are

(a) Voltage sources only

(b) Current sources only

(c) Resistors ,inductors and capacitors

(d) Both Voltage and Current sources
Ans: c

29. In D.C , inductor acts as

(a) Short circuit

(b) Open circuit

(c) both (a)&(b)

(d) none of these
Ans: a

30. In Unilateral Network the current flows in

(a) Unidirectional

(b) Bidirectional

(c) Rotational

(d) None of these
Ans: a

31. Workdone is

(a) F.d

(b) E/F

(c) IR

(d) None of these
Ans: a

32. Unit of Resistance is

(a) Ampere

(b) Volt

(c) Watt

(d) ohms
Ans: d

33. Unit of inductance is

(a) Ampere

(b) Volt

(c) Watt

(d) henry
Ans: d

34. Unit of capacitance is

(a) Ampere

(b) farad

(c) Watt

(d) henry
Ans: b

35. For high current applications which type of 3 phase circuit is Preferred

(a) Star

(b) Delta

(c) Star or Delta

(d) Neither Star nor Delta
Ans: a
36. For low voltage applications which type of 3 phase circuit to be Preferred

(a) Star

(b) Delta

(c) Star or Delta

(d) Neither Star nor Delta
Ans: a
37. Unit of charge is

(a) Ampere

(b) coulomb

(c) Watt

(d) henry
Ans: b
38. EMF is

(a) Election motion force

(b) Electrical motion force

(c) Electro motive force

(d) None of these
Ans: c

39. MMF is

(a) Magnetic motive force

(b) Magnetic motion force

(c) Magneto motive force

(d) None of these
Ans: c

40. Voltage-Current relationship in inductor element is

(a) In phase

(b) 90 (lead)

(c) 90 (lag)

(d) constant
Ans: c

41. Voltage-Current relationship in capacitor element is

(a) In phase

(b) 90 (lead)

(c) 90 (lag)

(d) constant
Ans: b

42. When two inductors are connected in series, equivalent inductance is

(a) L1+L2

(b) 1/(L1+L2)

(c) L1.L2

(d) None of these
Ans: a

43. When two capacitors are connected in series, equivalent capacitance is

(a) C1+C2

(b) 1/(C1+C2)

(c) L1.L2

(d) (1/c1)+(1/c2)
Ans: d

44. R.M.S Value of full wave rectified sinusoidal voltage is

(a) V_M/3

(b) V_M/2

(c) V_M/Ö2

(d) none of these
Ans:c
45. Form factor of full wave rectified sinusoidal voltage is

(a) 1.21

(b) 1.11

(c) 4.44

(d) none of these
Ans: b
46. Power factor for pure inductor

(a) 0(lead)

(b) 0

(c) 0(lag)

(d) none of these
Ans: c
47. Power factor for pure capacitor

(a) 0(lead)

(b) 0

(c) 0(lag)

(d) none of these
Ans: a
48. Frequency is defined as

(a) No of cycles/sec

(b) time/cycles

(c) 1/cycles

(d) None of these
Ans: a

49. In Series resistive circuit, voltage across each resistor is

(a) divided

(b) constant

(c) no change

(d) None of these
Ans: a

50. In Series resistive circuit current through each resistor is

(a) divided

(b) same

(c) 0

(d) None of these

Ans:b

51. When two inductors are connected in parallel, equivalent inductance is

(a) L1+L2

(b) (1/L1)+(1/L2)

(c) L1.L2

(d) None of these
Ans: b

52. When two capacitors are connected in parallel, equivalent capacitance is

(a) L1+L2

(b) (1/L1)+(1/L2)

(c) C1+C2

(d) None of these
Ans:c

53.A sinusoidal Wave form is

a)sine wave form

b) triangle wave form

c) both(a)&(b)

d)none of these
Ans:a

54. In 3 phase delta circuit, phase voltage is

(a) V_Ph =Ö3 V_L

(b) V_Ph = V_L /Ö3

(c) V_Ph = V_L

(d) V_Ph =3 V_L
Ans: c
55. In 3 phase star, line current is

(a) I_L =I _Ph

(b) I_L =2 I _Ph

(c) I_L =3 I _Ph

(d) I_L =Ö3 I _Ph
Ans:a
56.Average value of half wave rectified sine waveform is

a) Vm/?

b) 2Vm/?

c) Vm/2

d) none of these
Ans:a

56 Average value of full wave rectified sine waveform is

a) Vm/?

b) 2Vm/?

c) Vm/2

d) none of these
Ans:b

57 Form factor of half wave rectified sine waveform is

a) Vm/?

b) 2Vm/?

c) 1.57

d) none of these
Ans: c

58. Peak factor of half wave rectified sine waveform is

a) Vm/?

b) 2

c) Vm/2

d) none of these
Ans:b

59. Form factor of full wave rectified sine waveform is

a) 1.11

b) 2Vm/?

c) 1.57

d) none of these
Ans:a

60. Peak factor of full wave sinusoidal waveform is

a) Vm/?

b) square root of 2

c) Vm/2

d) none of these
Ans:b