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.

1.

With a total resistance of 3300 ohms and a 45 V source, if R is 1200 ohms, what will be its voltage drop?

A. 16.36 V
B. 32.72 V
C. 10.90 V
D. 15.00 V
Answer» B. 32.72 V
2.

Given a series circuit containing resistors of different values, which statement is ?

A. The current through each resistor is the same.
B. The sum of the voltage drops across each resistive element will be equal to source voltage.
C. The total resistance is the sum of the value of the resistors.
D. The voltage drop across each resistor is the same.
Answer» E.
3.

When 50 V is applied to four series resistors, 100 µA flows. If = 12 k , = 47 k, and = 57 k, what is the value of ?

A. 38.4 k
B. 3.84 k
C. 384 k
D. 3.84 M
Answer» D. 3.84 M
4.

If 7.3 k, 1.8 k, and 4.9 k resistors are wired in series, the total resistance is 14 k.

A. True
B. False
Answer» B. False
5.

is the reference point from which voltages are measured in an electronic circuit.

A. True
B. False
Answer» B. False
6.

Voltage sources are added when they are .

A. True
B. False
Answer» C.
7.

If four 9 V batteries are connected , the total voltage is 36 V.

A. True
B. False
Answer» B. False
8.

The total resistance is 35 .

A. True
B. False
Answer» B. False
9.

If a 47 and a 68 resistor are connected in series, the total resistance is ___.

A. 3,196
B. less than 47
C. less than 68
D. 115
Answer» E.
10.

If four 90 resistors are connected in series across an 18 V source, the current equals ___.

A. 50 mA
B. 0.2 A
C. 5 A
D. 20 A
Answer» B. 0.2 A
11.

If a 3.9 k, a 7.5 k, and a 5.6 k resistor are connected in series with a 34 V source, the voltage dropped across the 7.5 k resistor equals _____.

A. 34 V
B. 15 V
C. 7.8 V
D. 11.2 V
Answer» C. 7.8 V
12.

If a 220 , a 100 , and a 180 resistor are connected in series across a 12 V source, the circuit current equals ___.

A. 41.67 A
B. 120 mA
C. 500 A
D. 24 mA
Answer» E.
13.

Kirchhoff’s voltage law states that:

A. the sum of the voltage drops in a series circuit is equal to the total applied voltage
B. the algebraic sum of the resistances is equal to the sum of the voltages
C. the algebraic sum of the individual currents around a closed loop is zero
D. the voltages developed across each element in a series circuit are identical
Answer» B. the algebraic sum of the resistances is equal to the sum of the voltages
14.

–1.2 V, +15 V, and –6 V batteries are connected in series. The magnitude of total voltage is _________.

A. 7.8 V
B. 10.2 V
C. 22.2 V
D. 1.3 V
Answer» B. 10.2 V
15.

If five equal resistors are connected in series with a 20 V source, and a current of 400 µA is measured, each resistor equals ___.

A. 10 k
B. 50 k
C. 125
D. 20
Answer» B. 50 k
16.

When 50 V is applied to four series resistors, 100 µA flows. If R1 = 12 k , R2 = 47 k, and R3 = 57 k, what is the value of R4?

A. 38.4 k
B. 3.84 k
C. 384 k
D. 3.84 M
Answer» D. 3.84 M
17.

Series aiding is a term sometimes used to describe voltage sources of the same polarity in series.

A. True
B. False
Answer» B. False
18.

Two 1.5 V cells are connected series opposing across two 100 resistors in series. Total current flow is

A. 15 mA
B. 5 mA
C. 2 mA
D. 0 A
Answer» E.
19.

The total resistance of a circuit is 680 . The percentage of the total voltage appearing across a 47 resistor that makes up part of the total series resistance is

A. 68%
B. 47%
C. 69%
D. 6.91%
Answer» E.
20.

The following resistors (one each) are connected in a series circuit: 470 , 680 , 1 k, and 1.2 k. The voltage source is 20 V. Current through the 680 resistor is approximately

A. 60 mA
B. 30 mA
C. 6 mA
D. 300 mA
Answer» D. 300 mA
21.

A series circuit consists of a 4.7 k, a 12 k, and a 2.2 k resistor. The resistor that has the most voltage drop is

A. the 12 k
B. the 2.2 k
C. the 4.7 k
D. impossible to determine from the given information
Answer» B. the 2.2 k
22.

What happens to the current in the series circuit if the resistance is doubled?

A. It becomes half its original value
B. It becomes double its original value
C. It becomes zero
D. It becomes infinity
Answer» B. It becomes double its original value
23.

What is the voltage measured across a series short?

A. Infinite
B. Zero
C. The value of the source voltage
D. Null
Answer» C. The value of the source voltage
24.

Many resistors connected in series will?

A. Divide the voltage proportionally among all the resistors
B. Divide the current proportionally
C. Increase the source voltage in proportion to the values of the resistors
D. Reduce the power to zero
Answer» B. Divide the current proportionally
25.

A voltage across a series resistor circuit is proportional to?

A. The amount of time the circuit was on for
B. The value of the resistance itself
C. The value of the other resistances in the circuit
D. The power in the circuit
Answer» C. The value of the other resistances in the circuit
26.

What is the value of x if the current in the circuit is 5A?

A. 15 ohm
B. 25 ohm
C. 55 ohm
D. 75 ohm
Answer» B. 25 ohm
27.

If there are two bulbs connected in series and one blows out, what happens to the other bulb?

A. The other bulb continues to glow with the same brightness
B. The other bulb stops glowing
C. The other bulb glows with increased brightness
D. The other bulb also burns out
Answer» C. The other bulb glows with increased brightness
28.

Find the voltage across the 6 ohm resistor.

A. 150V
B. 181.6V
C. 27.27V
D. 54.48V
Answer» D. 54.48V
29.

Voltage across the 60ohm resistor is______

A. 72V
B. 0V
C. 48V
D. 120V
Answer» C. 48V
30.

In a series circuit, which of the parameters remain constant across all circuit elements such as resistor, capacitor and inductor etcetera?

A. Voltage
B. Current
C. Both voltage and current
D. Neither voltage nor current
Answer» C. Both voltage and current
31.

Find the current in the circuit.

A. 1 A
B. 2 A
C. 3 A
D. 4 A
Answer» C. 3 A
32.

Find the current in the circuit shown below.

A. 0.1
B. 0.2
C. 0.3
D. 0.4
Answer» D. 0.4
33.

In the circuit shown below determine the total impedance.

A. 161
B. 162
C. 163
D. 164
Answer» C. 163
34.

Determine the voltage across the resistor in the circuit shown below.

A. 3
B. 4
C. 5
D. 6
Answer» D. 6
35.

Find the voltage across the capacitor in the circuit shown below.

A. 7
B. 7.5
C. 8
D. 8.5
Answer» E.
36.

An AC voltage source supplies a 500Hz, 10V rms signal to a 2kΩ resistor in series with a 0.1µF capacitor as shown in the following figure. Find the total impedance.

A. 3750.6Ω
B. 3760.6Ω
C. 3780.6Ω
D. 3790.6Ω
Answer» C. 3780.6Ω
37.

Determine the source voltage if voltage across resistance is 70V and the voltage across inductor is 20V as shown in the figure.

A. 71
B. 72
C. 73
D. 74
Answer» D. 74
38.

In the circuit shown below, find voltage across inductive reactance.

A. 9.5
B. 10
C. 9
D. 10.5
Answer» B. 10
39.

In the circuit shown below, find the voltage across resistance.

A. 0.303
B. 303
C. 3.03
D. 30.3
Answer» D. 30.3
40.

Find the current I (mA) in the circuit shown below.

A. in the circuit shown below.a) 3.03
B. 30.3
C. 303
D. 0.303
Answer» B. 30.3
41.

The circuit shown below consists of a 1kΩ resistor connected in series with a 50mH coil, a 10V rms, 10 KHz signal is applied. Find impedance Z in rectangular form.

A. (1000+j0.05) Ω
B. (100+j0.5) Ω
C. (1000+j3140) Ω
D. (100+j3140) Ω
Answer» D. (100+j3140) Ω
42.

If we apply a sinusoidal input to RL circuit, the current in the circuit is __________ and the voltage across the elements is _______________

A. square, square
B. square, sinusoid
C. sinusoid, square
D. sinusoid, sinusoid
Answer» E.
43.

When is tanφ negative?

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» B. When inductive reactance is greater than capacitive reactance
44.

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 capacitive reactance in the circuit.

A. 316 ohm
B. 195 ohm
C. 124 ohm
D. 212 ohm
Answer» E.
45.

Which of the following is not ac waveform?

A. sinusoidal
B. square
C. constant
D. triangular
Answer» D. triangular
46.

In an RLC circuit, the power factor is always ____________

A. Positive
B. Negative
C. Depends on the circuit
D. Zero
Answer» D. Zero
47.

Can ohm’s law be applied in an ac circuit?

A. Yes
B. No
C. Depends on the rms current
D. Depends on the rms voltage
Answer» B. No
48.

The correct expression for the instantaneous current in a resistive circuit is?

A. i=Vm(sint)/R
B. i=Vm(cost)/R
C. i=V(sint)/R
D. i=V(cost)/R
Answer» B. i=Vm(cost)/R
49.

Calculate the resistance in the circuit if the rms voltage is 20V and the rms current is 2A.

A. 2 ohm
B. 5 ohm
C. 10 ohm
D. 20 ohm
Answer» D. 20 ohm
50.

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 current in the circuit.

A. 40 A
B. 10 A
C. 20 A
D. 30 A
Answer» D. 30 A