Explore topic-wise MCQs in Electronics.

This section includes 213 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics knowledge and support exam preparation. Choose a topic below to get started.

51.

Find the total voltage applied in a series RLC circuit when i=3mA, Vₗ=30V, Vc=18V and R=1000 ohms.

A. 3.95V
B. 51V
C. 32.67V
D. 6.67V
Answer» C. 32.67V
52.

In ac circuit, resistance 5 ohm is connected with a capacitor having capacitive reactance 12 ohm. Supply of 260 V is connected to the circuit. Calculate the voltage across a capacitor.

A. 300 V
B. 200 V
C. 240 V
D. 100 V
Answer» D. 100 V
53.

In which device inductor cannot be used?

A. filter circuit
B. transformer
C. choke
D. dielectric
Answer» E.
54.

Choke involve use of _____________

A. Resistor
B. Capacitor
C. Inductor
D. Transistor
Answer» D. Transistor
55.

Inductor does not allow sudden changes in?

A. Voltage
B. Current
C. Resistance
D. Inductance
Answer» C. Resistance
56.

What is the value of impedance at resonance?

A. Xₗ
B. Xc
C. R
D. 0
Answer» D. 0
57.

Which, among the following, is the correct expression for φ.

A. φ=tan¯¹ (XL/R)
B. φ=tan¯¹ (R/XL)
C. φ=tan¯¹ (XL*R)
D. φ=cos¯¹ (XL/R)
Answer» B. φ=tan¯¹ (R/XL)
58.

A resistance of 7 ohm is connected in series with an inductance of 31.8mH. The circuit is connected to a x V 50Hz sinusoidal supply. The current in the circuit is 8.2A. Calculate the value of x.

A. 10V
B. 50V
C. 100V
D. 120V
Answer» D. 120V
59.

A resistance of 7 ohm is connected in series with an inductance of 31.8mH. The circuit is connected to a 100V 50Hz sinusoidal supply. Calculate the voltage across the inductor.

A. 52V
B. 82V
C. 65V
D. 76V
Answer» C. 65V
60.

What is the real part of the impedance of RLC circuit?

A. Resistance
B. Conductance
C. Admittance
D. Reactance
Answer» B. Conductance
61.

The combination of resistance and reactance known as ___________

A. Susceptance
B. Impedance
C. Conductance
D. Admittance
Answer» C. Conductance
62.

In ac circuit, resistance 5 ohm is connected with capacitor having capacitive reactance 12 ohm. Supply of 260 V is connected to the circuit. Calculate the voltage across resistance.

A. 300 V
B. 200 V
C. 240 V
D. 100 V
Answer» E.
63.

Can capacitor fully charge using alternating current?

A. yes
B. no
C. may or may not
D. depend on value of capacitance
Answer» B. no
64.

What is the resonance condition?

A. When Xₗ>Xc
B. When Xₗ<Xc
C. When Xₗ=Xc
D. When Xc=infinity
Answer» D. When Xc=infinity
65.

In an AC circuit, resistance 50 Ω, inductance 0.3 H and capacitance 15 μF is connected to an AC voltage source 25 V, 50 Hz. Determine the inductive reactance in the circuit.

A. 36 ohm
B. 95 ohm
C. 125 ohm
D. 140 ohm
Answer» C. 125 ohm
66.

What is φ in terms of voltage?

A. φ=cos¯¹V/VR
B. φ=cos¯¹V*VR
C. φ=cos¯¹VR/V
D. φ=tan¯¹V/VR
Answer» D. φ=tan¯¹V/VR
67.

What is the current in an inductive circuit when the applied voltage is maximum?

A. Infinity
B. Maximum
C. Zero
D. Cannot be determined
Answer» D. Cannot be determined
68.

If in an alternating current circuit, capacitance of 30 µF is connected to a supply of 200V,50Hz. Find the current in the circuit.

A. 1.38 A
B. 1.89 A
C. 1.74 A
D. 0.89 A
Answer» B. 1.89 A
69.

What is the value of current in an inductive circuit when there is no applied voltage?

A. Minimum
B. Maximum
C. Zero
D. Cannot be determined
Answer» C. Zero
70.

Inductance is _____________________ to number of turns in the coil.

A. directly proportional
B. inversely proportional
C. equal
D. not related
Answer» B. inversely proportional
71.

In an AC circuit, resistance 50 Ω, inductance 0.3 H and capacitance 15 μF is connected to an AC voltage source 25 V, 50 Hz. Determine the phase difference between current and voltage.

A. 670
B. 540
C. 470
D. 770
Answer» B. 540
72.

What is the resistance offered by a capacitor?

A. Susceptance
B. Conductance
C. Admittance
D. Reactance
Answer» E.
73.

In an AC circuit, resistance 50 Ω, inductance 0.3 H and capacitance 15 μF is connected to an AC voltage source 25 V, 50 Hz. Determine the impedance in the circuit.

A. 110 ohm
B. 100 ohm
C. 125 ohm
D. 140 ohm
Answer» D. 140 ohm
74.

A resistance of 7 ohm is connected in series with an inductance of 31.8mH. The circuit is connected to a 100V 50Hz sinusoidal supply. Calculate the phase difference.

A. -55.1
B. 55.1
C. 66.1
D. -66.1
Answer» B. 55.1
75.

What is not a frequency for ac current?

A. 50 Hz
B. 55 Hz
C. 0Hz
D. 60 Hz
Answer» D. 60 Hz
76.

In an RLC series phasor, we start drawing the phasor from which quantity?

A. Voltage
B. Resistance
C. Impedance
D. Current
Answer» E.
77.

When is tanφ positive?

A. When inductive reactance is less than capacitive reactance
B. When inductive reactance is greater than capacitive reactance
C. When inductive reactance is equal to capacitive reactance
D. When inductive reactance is zero
Answer» C. When inductive reactance is equal to capacitive reactance
78.

Which type of current can be stored in a capacitor?

A. Alternating current
B. Direct current
C. Both alternating current and direct current
D. Neither alternating current nor direct current
Answer» C. Both alternating current and direct current
79.

In an RLC circuit, which of the following is always used as a vector reference?

A. Voltage
B. Resistance
C. Impedance
D. Current
Answer» B. Resistance
80.

In an AC circuit, resistance 50 Ω, inductance 0.3 H and capacitance 15 μF is connected to an AC voltage source 25 V, 50 Hz. Determine the current in the circuit.

A. 0.01 A
B. 0.2 A
C. 0.02 A
D. 0.002 A
Answer» C. 0.02 A
81.

For an RL circuit, the phase angle is always ________

A. Positive
B. Negative
C. 0
D. 90
Answer» C. 0
82.

If in an alternating current circuit, capacitance C is connected to a supply of 200V,50Hz. Current in the circuit is 1.89 A. Find the capacitance C.

A. 30 µF
B. 20 µF
C. 10 µF
D. 15 µF
Answer» B. 20 µF
83.

What is the frequency in resonance condition?

A. Minimum
B. Maximum
C. Cannot be determined
D. Zero
Answer» C. Cannot be determined
84.

What is tanϕ for RC circuit?

A. Xc/R
B. Xₗ/R
C. R/Z
D. Z/R
Answer» B. Xₗ/R
85.

If in an alternating current circuit, impedance is 26 ohm, capacitive reactance is 24 ohm, what is the resistance?

A. 25 ohm
B. 10 ohm
C. 12 ohm
D. 23 ohm
Answer» C. 12 ohm
86.

If in an alternating current circuit, resistance is 5 ohm, capacitive reactance is 12 ohm, what is the impedance?

A. 5 ohm
B. 10 ohm
C. 12 ohm
D. 13 ohm
Answer» E.
87.

The correct expression for the instantaneous current if instantaneous voltage is Vm(sint) in an inductive circuit is?

A. i = Vm(sint)/Xₗ
B. i = Vm(cost)/Xₗ
C. i = -Vm(sint)/Xₗ
D. i = -Vm(cost)/Xₗ
Answer» E.
88.

A resistance of 7 ohm is connected in series with an inductance of 31.8mH. The circuit is connected to a 100V 50Hz sinusoidal supply. Calculate the voltage across the resistor.

A. 31.8V
B. 57.4V
C. 67.3V
D. 78.2V
Answer» C. 67.3V
89.

A resistance of 7 ohm is connected in series with an inductance of 31.8mH. The circuit is connected to a 100V 50Hz sinusoidal supply. Calculate the current in the circuit.

A. 2.2A
B. 4.2A
C. 6.2A
D. 8.2A
Answer» E.
90.

What value of direct current must flow through a resistor to produce the same heating power as an alternating current with a peak value of 3.5 A?

A. 1.5 A
B. 2.5 A
C. 3.5 A
D. 4.5 A
Answer» C. 3.5 A
91.

What is imaginary part of the impedance of RLC circuit?

A. Resistance
B. Conductance
C. Admittance
D. Reactance
Answer» E.
92.

In an inductive circuit, the current________ the voltage?

A. Leads
B. Lags
C. Is greater than
D. Is less than
Answer» C. Is greater than
93.

What is impedance at resonance?

A. maximum
B. minimum
C. zero
D. cannot be determined
Answer» C. zero
94.

What is sinϕ from impedance triangle?

A. Xₗ/R
B. Xₗ/Z
C. R/Z
D. Z/R
Answer» C. R/Z
95.

The correct expression for the instantaneous current if instantaneous voltage is Vm(sint) in a resistive circuit is?

A. 1A
B. 2A
C. 3A
D. 4A
Answer» C. 3A
96.

What is the resonance frequency of ac circuit?

A. 1/√LC
B. √(L/C)
C. √LC
D. LC
Answer» B. √(L/C)
97.

What is the relation between reactance, resistance and impedance?

A. Z=R+jX
B. Z=R+X
C. Z=R-X
D. Z=R-jX
Answer» B. Z=R+X
98.

In an inductive circuit, the voltage_______ the current?

A. Leads
B. Lags
C. Is greater than
D. Is less than
Answer» B. Lags
99.

What is the correct expression for the phase angle in an RLC series circuit?

A. a
B. b
C. c
D. d
Answer» B. b
100.

Which type of ac waveform is given in figure?

A. sinusoidal
B. triangular
C. square
D. complex waveform
Answer» B. triangular