1. The advantage of the double squirrel cage induction motor over a single cage rotor is that its _______
Efficiency is higher
Power factor is higher
Slip is larger
Starting current is lower

2. A 16-pole 3-phase 60 Hz induction motor is operating at a speed of 150 rpm. The frequency of the rotor current of the motor in Hz is __________
20
40
30
10

3. Calculate the amplitude of the sinusoidal waveform
710
715
716
718

4. R.M.S value of the sinusoidal waveform V=48sin(6.5?t+89?�46.8).
33.94 V
33.56 V
33.12 V
33.78 V

5. The short circuit test on a 3-? induction motor is conducted at a rotor speed of _______
Zero
< Ns
> Ns
Ns

6. If induction motor air gap power is 10 KW and mechanically developed power is 8 KW then rotor ohmic loss will be _________ KW.
1
2
3
4

7. A 3-phase induction machine draws active power P and reactive power Q from the grid. If it is operated as a generator then P and Q will be _________
Positive and Negative
Negative and Positive
Positive and Positive
Negative and Negative

8. The slope of the V-I curve is 39.1�. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.
.81 ?
.36 ?
.75 ?
.84 ?

9. If induction motor air gap power is 48 KW and gross developed power is 28 KW then rotor ohmic loss will be _________ KW.
10
20
30
40

10. The power factor of a squirrel cage induction motor is ___________
Low at light load only
Low at heavy loads only
Low at the light and heavy loads both
Low at rate load only

11. Calculate the active power in a .154 H inductor.
22 W
14 W
45 W
0 W

12. Calculate the time period of the waveform z(t)=24sin(?t+?�4)+4sin(2?t+?�6).
2 sec
3 sec
4 sec
1 sec

13. Calculate the total heat dissipated in a resistor of 50 ? when 1.4 A current flows through it.
98 W
92 W
91 W
93 W

14. Calculate mark to space ratio if the system is on for 26.3 sec and off for 24.2 sec.
1.086
1.042
1.214
1.876

15. In the chopper circuit commutation times are _______
Current commutation is equal to voltage commutation
Current commutation is less as compared to that of voltage commutation
Current commutation is more as compared to that of voltage commutation
Both commutation techniques are not comparable

16. The generated e.m.f from 4-pole armature having 1 conductors driven at 1 rev/sec having flux per pole as 10 Wb with wave winding is ___________
30 V
40 V
70 V
20 V

17. Calculate the moment of inertia of the sphere having a mass of 8.4 kg and radius of 61 cm.
3.124 kgm2
3.125 kgm2
4.545 kgm2
5.552 kgm2

18. The most suitable control-motor application is __________
AC shunt motor
DC separately motor
AC one-phase induction motor
DC shunt motor

19. In a DC series motor the e.m.f developed is proportional to _______
N�Ia
N�Ia2
N�Ia3
N�Ia.5

20. Calculate the value of the time period if the frequency of the signal is .07 sec.
14.28 sec
14.31 sec
14.23 sec
14.78 sec

21. The slope of the V-I curve is 13.89�. Calculate the value of resistance.
.247 ?
.345 ?
.231 ?
.222 ?

22. In a DC shunt motor the e.m.f developed is proportional to ___________
Ia
Ia2
Ia3
Iao

23. Calculate the power factor angle during the resonance condition.
0�
10�
80�
90�

24. Calculate the value of the duty cycle if the system is on for 5 sec and off for inf sec.12.
0
0.4
0.2
0.1

25. Calculate the value of the frequency of the AC supply in India.
0 Hz
50 Hz
49 Hz
60 Hz

26. What is the formula for the maximum active power in the cylindrical rotor synchronous machine? (Eb represents armature emf Vt represents terminal voltage ? represents rotor angle X represents reactance)
Eb�Vt�sin?�X
Eb�Vt2�X
Eb2�Vt�sin?�X
Eb�Vt�X

27. Calculate the power factor if the power angle is 36.86�.
0.8
0.4
0.6
1

28. Calculate the reactive power in a 2.2 ? resistor.
1.5 VAR
2.6 VAR
0 VAR
1.9 VAR

29. What is the unit of the distance?
m
m/s
atm/m
Volt

30. Calculate the reactive power in a 7.2545 ? resistor.
1.221 VAR
2.611 VAR
0 VAR
1.997 VAR

31. The slope of the V-I curve is 180o. Calculate the value of resistance. The graph is parallel to the x-axis.9.
1.47 ?
1.81 ?
0 ?
4.12 ?

32. Calculate the value of the duty cycle if the system is on for 1 sec and off for 0 sec.1
1
0.4
0.1
0.6

33. The phase difference between voltage and current in the choke coil.
90�
40�
50�
68�

34. A 32-pole 3-phase 70 Hz induction motor is operating at a speed of 112 rpm. The frequency of the rotor current the motor in Hz is __________
40.2
46.1
40.1
40.6

35. A 20-pole 3-phase 90 Hz induction motor is operating at a speed of _______ rpm. The frequency of the rotor current of the motor in Hz is 20.
418.56
420.12
421.23
422.45

36. Calculate the amplitude of the sinusoidal waveform z(t)=.27sin(.369?t+.142?�4.25).
0.287
0.27
0.287
0.216

37. R.M.S value of the sinusoidal waveform q(t)=2.11cos(87.25t+78?�478.23).
1.49 V
1.56 V
1.12 V
1.78 V

38. The no-load circuit test on a 3-? induction motor is conducted at a rotor speed of _______
Zero
< Ns
> Ns
Ns

39. If induction motor air gap power is 67 KW and mechanically developed power is 26 KW then rotor ohmic loss will be _________ KW.
41
42
43
44

40. Calculate the line voltage in star connection when phase voltage=45 V.
77.9 V
77.6 V
77.2 V
77.8 V

41. The slope of the V-I curve is 1.1�. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.
.019 ?
.036 ?
.075 ?
.084 ?

42. If induction motor rotor power is 157.5 KW and gross developed power is 79.9 KW then rotor ohmic loss will be _________ KW.
77.5
77.6
76.9
77.1

43. The power factor of a squirrel cage induction motor generally is ___________
.6-.8
.1-.2
.2-.4
.5-.7

44. Calculate the active power in a .89 H inductor.
1.535 W
0 W
2.484 W
1.598 W

45. Calculate the time period of the waveform i(t)=sin(?t+6?�4)+sin(?t+5?�6).
2 sec
4 sec
5 sec
3 sec

46. Calculate the total heat dissipated in a rotor resistor of 14.23 ? when .65 A current flows through it.
6.45 W
6.01 W
6.78 W
6.98 W

47. Calculate mark to space ratio if the system is on for 4.3 sec and off for 78.2 sec.
0.054
0.047
0.039
0.018

48. In the rotor voltage injection method when an external voltage source is in phase with the main voltage then speed will ___________
Increase
Decrease
Remain unchanged
First increases then decrease

49. A 2-pole 3-phase ______ Hz induction motor is operating at a speed of 550 rpm. The frequency of the rotor current of the motor in Hz is 2.
9.98
9.71
9.12
9.37

50. Calculate the average value of the sinusoidal waveform x(t)=848sin(1.65?t+2?�0.68).
0
78 V
15 V
85 V

51. R.M.S value of the periodic square waveform of amplitude 72 V.
72 V
56 V
12 V
33 V

52. In the rotor voltage injection method when an external voltage source is in opposite phase with the main voltage then speed will ___________
Increase
Decrease
Remain unchanged
First increases then decrease

53. The slope of the V-I curve is 9.1�. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.
16 ?
26 ?
25 ?
44 ?

54. If induction motor air gap power is 1.8 KW and gross developed power is .1 KW then rotor ohmic loss will be _________ KW.
1.7
2.7
3.7
4.7

55. The power factor of a squirrel cage induction motor is ___________
High at light load only
High at heavy loads only
Low at the light and heavy loads both
Low at rate load only

56. At low values of slip the electromagnetic torque is directly proportional to ___________
s
s2
s3
s4

57. Calculate the time period of the waveform v(t)=12sin(8?t+8?�15)+144sin(2?t+?�6)+ 445sin(?t+7?�6).
8 sec
4 sec
7 sec
3 sec

58. Calculate the total heat dissipated in a resistor of 44 ? when 0 A current flows through it.
0 W
2 W
1.5 W
.3 W

59. The value of slip at which maximum torque occurs ________
R2�X2
4R2�X2
2R2�X2
R2�3X2

60. Calculate the voltage regulation in the synchronous machine if the no-load voltage is 12 V and the full load voltage is 15V.
-20%
-40%
-60%
-80%

61. Calculate the condition for maximum voltage regulation in the synchronous machine.
?=?s
?=2?s
?=4?s
?=8?s

62. R.M.S value of the sinusoidal waveform v(t)=211sin(7.25t+7?�78.3).
149.19 V
156.23 V
116.57 V
178.64 V

63. Calculate the peak value of sinusoidal waveform if the r.m.s value is 21 V.29.69 V
29.69 V
48.74 V
69.23 V
25.74 V

64. If induction motor air gap power is 2 KW and mechanically developed power is 1 KW then rotor ohmic loss will be _________ KW.7.
1
2
3
4

65. Calculate the line voltage in the delta connection when phase voltage=45 V.
46 V
47 V
45 V
78 V

66. The slope of the V-I curve is 35.48�. Calculate the value of resistance. Assume the relationship between voltage and current is a straight line.
0.452 ?
0.462 ?
0.752 ?
0.712 ?

67. Calculate the line current in the delta connection when phase current=17 A.
29.44 A
24.64 A
23.48 A
26.56 A

68. Calculate the active power in a 168.12 H inductor.
65 W
0 W
68 W
64 W

69. Calculate the maximum value of slip when rotor resistance is 2 ? and rotor reactance is 3 ?.
0.66
0.33
0.44
0.99

70. Calculate the total heat dissipated in a rotor resistor of 21 ? when .81 A current flows through it.
13.77 W
12.56 W
46.45 W
13.98 W

71. Calculate the active power in an 8.12 F capacitor.
89 W
41 W
0 W
48 W