1. A sine wave has a frequency of 50 Hz. Its angular frequency is _______ radian/second.
2. The reactance offered by a capacitor to alternating current of frequency 50 Hz is 20 Q. If frequency is increased to 100 Hz, reactance becomes_____ohms.
3. The period of a wave is ______.
4. The form factor is the ratio of ________.
5. The period of a sine wave is _____ seconds. Its frequency is
7. A heater is rated as 230 V, 10 kW, A.C. The value 230 V refers to ______.
8. If two sinusoids of the same frequency but of different amplitudes and phase angles are subtracted, the resultant is
9. The peak value of a sine wave is 200 V. Its average value is
10. If two sine waves of the same frequency have a phase difference of JT radians, then
12. Two waves of the same frequency have opposite phase when the phase angle between them is
13. The power consumed in a circuit element will be least when the phase difference between the current and voltage is
14. The r.m.s. value and mean value is the same in the case of
15. For the same peak value which of the following wave will 'have the highest r.m.s. value ?
16. For the same peak value, which of the following wave has the least mean value ?
17. For a sine wave with peak value Imax the r.m.s. value is
18. Form Factor is the ratio of ________.
19. Form factor for a sine wave is ________.
20. For a sine wave with peak value Emax______30. the average value is
21. For a frequency of 200 Hz, the time period will be
22. The phase difference between voltage and current wave through a circuit element is given as 30°. The essential condition is that
23. The r.m.s. value of a sinusoidal A.C. current is equal to its value at an angle of ______ degrees.
24. Capacitive reactance is more when
25. In a series resonant circuit, the impedance of the circuit is
26. Power factor of an electrical circuit is equal to
27. The best place to install a capacitor is
28. Poor power factor is ________.
29. Capacitors for power factor correction are rated in
30. In series resonant circuit, increasing inductance to its twice value and reducing capacitance to its half value
31. Pure inductive circuit
32. Inductance affects the direct current flow
33. Inductance of a coil Varies
34. All the rules and laws of D.C. circuit also apply to A.C. circuit containing
35. Time constant of an inductive circuit
36. Power factor of an inductive circuit is usually improved by connecting capacitor to it in
37. In a highly capacitive circuit the
38. Power factor of the following circuit will be zero
39. Power factor of the following circuit will be unity
40. Power factor of the system is kept high
41. The time constant of the capacitance circuit is defined as the time during which voltage
42. In a loss-free R-L-C circuit the transient current is
43. The r.m.s. value of alternating current is given by steady (D.C.) current which when flowing through a given circuit for a given time produces
44. The square waveform of current has following relation between r.m.s. value and average value.
45. The double energy transient occur in the
46. The transient currents are associated with the
47. The power factor at resonance in R-L- C parallel circuit is
48. In the case of an unsymmetrical alternating current the average value must always be taken over
49. In a pure resistive circuit
50. In a pure inductive circuit
51. In a circuit containing R, L and C, power loss can take place in
52. Inductance of coil
53. In any A.C. circuit always
54. Which of the following circuit component opposes the change in the circuit voltage ?
55. In a purely inductive circuit
56. Power factor of electric bulb is
57. Pure inductive circuit takes power from the A.C. line when
58. Time constant of a circuit is the time in seconds taken after the application of voltage to each
59. Time constant of an inductive circuit
60. Time constant of a capacitive circuit
61. Magnitude of current at resonance in R-L-C circuit
62. In a R-L-C circuit
63. In R-L-C series resonant circuit magnitude of resonance frequency can be changed by changing the value of
64. In a series L-C circuit at the resonant frequency the
65. The time constant of a series R-C circuit is given by
66. If resistance is 20 Q. and inductance is 27 in a R-L series circuit, then time constant of this circuit will be
67. Which of the following coil will have large resonant frequency ?
68. If a sinusoidal wave has frequency of 50 Hz with 30 A r.m.s. current which of the following equation represents this wave ?
69. The safest value of current the human body can carry for more than 3 second is
70. A pure inductance connected across 250 V, 50 Hz supply consumes 100 W.
This consumption can be attributed to
71. The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA
The power drawn by the circuit is
72. The effective resistance of an iron-cored choke working on ordinary supply frequency is more than its true resistance because of
73. In an AC. circuit, a low value of kVAR compared with kW indicates
74. In AC. circuits, laminated iron is invariably used in order to
75. The ratio of active power to apparent power is known as factor.
76. All definitions of power factor of a series R-L-C circuit are correct except
77. The apparent power drawn by an A.C. circuit is 10 kVA and active power is 8 kW. The reactive power in the circuit is
78. What will be the phase angle between two alternating waves of equal frequency, when one wave attains maximum value the other is at zero value ?
79. The purpose of a parallel circuit resonance is to magnify
80. In an A.C. circuit power is dissipated in
81. In a parallel R-C circuit, the current always______the applied voltage
82. At very low frequencies a series R-C circuit behaves as almost purely
83. Skin effect occurs when a conductor carries current at frequencies.
84. At ______ frequencies the parallel R-L circuit behaves as purely resistive.
85. In a sine wave the slope is constant
86. The power is measured in terms of decibles in case of
87. Capacitive susceptance is a measure of
88. Which of the following statements pertains to resistors only ?
89. Which of the following refers to a parallel circuit ?
90. Aphasoris
91. A parallel AC. circuit in resonance will
92. Wire-wound resistors are unsuitable for use at high frequencies because they
93. The inductance of a coil can be increased by
94. In a three-phase supply floating neutral is undesirable because it way give rise to
95. Which of the following waves has the highest value of peak factor ?
96. The frequency of domestic power supply in India is
97. The r.m.s. value of half wave rectified sine wave is 200 V. The r.m.s. value of full wave rectified AC. will be
98. The r.m.s. value of pure cosine function is
99. Ohm is unit of all of the following except
100. The series and parallel resonance on L-C circuit differs in that
101. The phasors for which of the following pair are 180° out of phase for VL, VC and VR?
102. The frequency of an alternating current is
103. A pure capacitor connected across an A.C. voltage consumed 50 W. This is due to
104. The power factor of a D.C. circuit is always
105. The product of apparent power and cosine of the phase angle between circuit voltage and current is
106. The equation of 50 Hz current sine wave having r.m.s. value of 60 A is
107. An A.C. voltage is impressed across a pure resistance of 3.5 ohms in parallel with a pure inductance of impedance of 3.5 ohms,
108. In a pure inductive circuit if the supply frequency is reduced to 1/2, the current will
109. In a pure capacitive circuit if the supply frequency is reduced to 1/2, the current will
110. When an alternating current passes through an ohmic resistance the electrical power converted into heat is
111. In each of the three coils of a three phase generator, an alternating voltage having an r.m.s. value of 220 V is induced. Which of the following values is indicated by the voltmeters ?
2. The reactance offered by a capacitor to alternating current of frequency 50 Hz is 20 Q. If frequency is increased to 100 Hz, reactance becomes_____ohms.
3. The period of a wave is ______.
4. The form factor is the ratio of ________.
5. The period of a sine wave is _____ seconds. Its frequency is
7. A heater is rated as 230 V, 10 kW, A.C. The value 230 V refers to ______.
8. If two sinusoids of the same frequency but of different amplitudes and phase angles are subtracted, the resultant is
9. The peak value of a sine wave is 200 V. Its average value is
10. If two sine waves of the same frequency have a phase difference of JT radians, then
12. Two waves of the same frequency have opposite phase when the phase angle between them is
13. The power consumed in a circuit element will be least when the phase difference between the current and voltage is
14. The r.m.s. value and mean value is the same in the case of
15. For the same peak value which of the following wave will 'have the highest r.m.s. value ?
16. For the same peak value, which of the following wave has the least mean value ?
17. For a sine wave with peak value Imax the r.m.s. value is
18. Form Factor is the ratio of ________.
19. Form factor for a sine wave is ________.
20. For a sine wave with peak value Emax______30. the average value is
21. For a frequency of 200 Hz, the time period will be
22. The phase difference between voltage and current wave through a circuit element is given as 30°. The essential condition is that
23. The r.m.s. value of a sinusoidal A.C. current is equal to its value at an angle of ______ degrees.
24. Capacitive reactance is more when
25. In a series resonant circuit, the impedance of the circuit is
26. Power factor of an electrical circuit is equal to
27. The best place to install a capacitor is
28. Poor power factor is ________.
29. Capacitors for power factor correction are rated in
30. In series resonant circuit, increasing inductance to its twice value and reducing capacitance to its half value
31. Pure inductive circuit
32. Inductance affects the direct current flow
33. Inductance of a coil Varies
34. All the rules and laws of D.C. circuit also apply to A.C. circuit containing
35. Time constant of an inductive circuit
36. Power factor of an inductive circuit is usually improved by connecting capacitor to it in
37. In a highly capacitive circuit the
38. Power factor of the following circuit will be zero
39. Power factor of the following circuit will be unity
40. Power factor of the system is kept high
41. The time constant of the capacitance circuit is defined as the time during which voltage
42. In a loss-free R-L-C circuit the transient current is
43. The r.m.s. value of alternating current is given by steady (D.C.) current which when flowing through a given circuit for a given time produces
44. The square waveform of current has following relation between r.m.s. value and average value.
45. The double energy transient occur in the
46. The transient currents are associated with the
47. The power factor at resonance in R-L- C parallel circuit is
48. In the case of an unsymmetrical alternating current the average value must always be taken over
49. In a pure resistive circuit
50. In a pure inductive circuit
51. In a circuit containing R, L and C, power loss can take place in
52. Inductance of coil
53. In any A.C. circuit always
54. Which of the following circuit component opposes the change in the circuit voltage ?
55. In a purely inductive circuit
56. Power factor of electric bulb is
57. Pure inductive circuit takes power from the A.C. line when
58. Time constant of a circuit is the time in seconds taken after the application of voltage to each
59. Time constant of an inductive circuit
60. Time constant of a capacitive circuit
61. Magnitude of current at resonance in R-L-C circuit
62. In a R-L-C circuit
63. In R-L-C series resonant circuit magnitude of resonance frequency can be changed by changing the value of
64. In a series L-C circuit at the resonant frequency the
65. The time constant of a series R-C circuit is given by
66. If resistance is 20 Q. and inductance is 27 in a R-L series circuit, then time constant of this circuit will be
67. Which of the following coil will have large resonant frequency ?
68. If a sinusoidal wave has frequency of 50 Hz with 30 A r.m.s. current which of the following equation represents this wave ?
69. The safest value of current the human body can carry for more than 3 second is
70. A pure inductance connected across 250 V, 50 Hz supply consumes 100 W.
This consumption can be attributed to
71. The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA
The power drawn by the circuit is
72. The effective resistance of an iron-cored choke working on ordinary supply frequency is more than its true resistance because of
73. In an AC. circuit, a low value of kVAR compared with kW indicates
74. In AC. circuits, laminated iron is invariably used in order to
75. The ratio of active power to apparent power is known as factor.
76. All definitions of power factor of a series R-L-C circuit are correct except
77. The apparent power drawn by an A.C. circuit is 10 kVA and active power is 8 kW. The reactive power in the circuit is
78. What will be the phase angle between two alternating waves of equal frequency, when one wave attains maximum value the other is at zero value ?
79. The purpose of a parallel circuit resonance is to magnify
80. In an A.C. circuit power is dissipated in
81. In a parallel R-C circuit, the current always______the applied voltage
82. At very low frequencies a series R-C circuit behaves as almost purely
83. Skin effect occurs when a conductor carries current at frequencies.
84. At ______ frequencies the parallel R-L circuit behaves as purely resistive.
85. In a sine wave the slope is constant
86. The power is measured in terms of decibles in case of
87. Capacitive susceptance is a measure of
88. Which of the following statements pertains to resistors only ?
89. Which of the following refers to a parallel circuit ?
90. Aphasoris
91. A parallel AC. circuit in resonance will
92. Wire-wound resistors are unsuitable for use at high frequencies because they
93. The inductance of a coil can be increased by
94. In a three-phase supply floating neutral is undesirable because it way give rise to
95. Which of the following waves has the highest value of peak factor ?
96. The frequency of domestic power supply in India is
97. The r.m.s. value of half wave rectified sine wave is 200 V. The r.m.s. value of full wave rectified AC. will be
98. The r.m.s. value of pure cosine function is
99. Ohm is unit of all of the following except
100. The series and parallel resonance on L-C circuit differs in that
101. The phasors for which of the following pair are 180° out of phase for VL, VC and VR?
102. The frequency of an alternating current is
103. A pure capacitor connected across an A.C. voltage consumed 50 W. This is due to
104. The power factor of a D.C. circuit is always
105. The product of apparent power and cosine of the phase angle between circuit voltage and current is
106. The equation of 50 Hz current sine wave having r.m.s. value of 60 A is
107. An A.C. voltage is impressed across a pure resistance of 3.5 ohms in parallel with a pure inductance of impedance of 3.5 ohms,
108. In a pure inductive circuit if the supply frequency is reduced to 1/2, the current will
109. In a pure capacitive circuit if the supply frequency is reduced to 1/2, the current will
110. When an alternating current passes through an ohmic resistance the electrical power converted into heat is
111. In each of the three coils of a three phase generator, an alternating voltage having an r.m.s. value of 220 V is induced. Which of the following values is indicated by the voltmeters ?
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