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.

151.

Voltage sources are added when they are series-opposing.

A. 1
B.
Answer» C.
Discussion
152.

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

A. 1
B.
Answer» B.
Discussion
153.

The sum of the voltage drops across series resistors must equal the total voltage applied.

A. 1
B.
Answer» B.
Discussion
154.

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

A. 3196
B. less than 47
C. less than 68
D. 115
Answer» E.
Discussion
155.

In a series circuit, the current flowing out of a resistor won't always equal the current flowing into that resistor.

A. 1
B.
Answer» C.
Discussion
156.

A voltage divider is always a _____

A. series-parallel circuit
B. series circuit
C. parallel circuit
D. bridge circuit
Answer» C. parallel circuit
Discussion
157.

–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
Discussion
158.

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
Discussion
159.

A series circuit current:

A. remains the same through each component
B. is the same as the individual resistances
C. is subtracted by each component
D. varies through each component
Answer» B. is the same as the individual resistances
Discussion
160.

Given a series circuit containing resistors of different values, which statement is not true?

A. The current through each resistor is the same.
B. The sum of the voltage drops across each resistive element will be equal.
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.
Discussion
161.

In the given circuit, what type of failure will cause the voltage at point B to equal the voltage at point C?

A. R1 shorts
B. R2 shorts
C. R3 shorts
D. R2 opens
Answer» C. R3 shorts
Discussion
162.

With 20 V applied, an 8-ohm resistor is in series with a lamp. When the lamp is removed, what voltage will be read across the lamp socket?

A. 0 V
B. 8 V
C. 12 V
D. 20 V
Answer» E.
Discussion
163.

What is the total power in the circuit?

A. 170 mW
B. 1.7 W
C. 17 W
D. 170 W
Answer» B. 1.7 W
Discussion
164.

The total circuit power in the given circuit equals _____.

A. 64 µW
B. 4 µW
C. 0 W
D. 16 × 10–12 W
Answer» B. 4 ¬µW
Discussion
165.

The sum of all the voltage drops in a series circuit equals the source voltage.

A. 1
B.
C. 1
D.
Answer» B.
Discussion
166.

With a 900 V source, voltage is divided across 3 series resistors of 300 V, 280 V, and:

A. 30 V
B. 270 V
C. 320 V
D. 900 V
Answer» D. 900 V
Discussion
167.

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.
Discussion
168.

A series circuit schematic is recognized because all the components are connected:

A. diagonally across the page
B. in a uniform vertical manner
C. end to end in a "string"
D. horizontally across the page
Answer» D. horizontally across the page
Discussion
169.

If R2 opens in the given circuit, what is the voltage at point B?

A. +19.2 V
B. +8.8 V
C. +28 V
D. –19.2 V
Answer» D. ‚Äì19.2 V
Discussion
170.

If series current doubles, then:

A. resistance is halved
B. voltage is doubled
C. voltage is reduced
D. resistance is doubled
Answer» B. voltage is doubled
Discussion
171.

Calculate the voltage at point C in the given circuit.

A. +1.48 V
B. +0.94 V
C. +11.6 V
D. +3 V
Answer» D. +3 V
Discussion
172.

The total resistance of a series circuit always depends on the highest value resistor in that circuit.

A. 1
B.
Answer» C.
Discussion
173.

If two resistors have the same voltage drop in a series circuit, it means:

A. they are connected in parallel
B. they are of unequal value
C. the voltage has doubled
D. they are of equal value
Answer» E.
Discussion
174.

What are the minimum and maximum output voltages?

A. 0 V, 4 V
B. 0 V, 8 V
C. 0 V, 12 V
D. 0 V, 16 V
Answer» E.
Discussion
175.

The total power dissipated in a series resistive circuit exceeds the sum of the resistor powers.

A. 1
B.
C. 1
D.
Answer» C. 1
Discussion
176.

If three resistors of 1.5 kilohms, 470 ohms, and 3300 ohms are in series with a 25-volt source, what is the total circuit current?

A. 210 mA
B. 5.2 mA
C. 4.7 mA
D. .007 A
Answer» D. .007 A
Discussion
177.

If 5 V and 16 V power supplies are connected in series-opposing, what is the total voltage?

A. 11 V
B. 16 V
C. 21 V
D. 80 V
Answer» B. 16 V
Discussion
178.

What is the voltage at points B to D in the given circuit?

A. +19.2 V
B. +8.8 V
C. +28 V
D. –19.2 V
Answer» B. +8.8 V
Discussion
179.

If series resistors dissipate 16 mW, 107 mW, 146 mW, and 243 mW, what is the total power consumed by the circuit?

A. 128 mW
B. 269 mW
C. 512 mW
D. 1024 mW
Answer» D. 1024 mW
Discussion
180.

Resistance in a series circuit will:

A. control the voltage
B. double the current
C. halve the power
D. oppose current
Answer» E.
Discussion
181.

In a series circuit, the voltage measured across a short will be:

A. source voltage
B. infinite voltage
C. zero volts
D. the normal voltage drop
Answer» D. the normal voltage drop
Discussion
182.

Calculate the voltage at point B in the given circuit.

A. +10.48 V
B. +0.94 V
C. +2.6 V
D. +3 V
Answer» B. +0.94 V
Discussion
183.

When a battery is connected to a series circuit, it delivers current based only upon:

A. primary/secondary difference
B. total resistance
C. the polarity connections
D. average resistance
Answer» C. the polarity connections
Discussion
184.

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
Discussion
185.

In a series circuit, larger resistances drop larger voltages.

A. 1
B.
C. 1
D.
Answer» B.
Discussion
186.

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
Discussion
187.

These components are in series.

A. 1
B.
Answer» B.
Discussion
188.

In the given circuit, the voltage dropped across R3 equals ___.

A. 1.5 V
B. 3 V
C. 6 V
D. More information is needed to find the voltage dropped across R3.
Answer» B. 3 V
Discussion
189.

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
Discussion
190.

The voltage drop across a series resistor is proportional to what other value?

A. total resistance
B. its own resistance
C. wattage rating
D. the amount of time the circuit is on
Answer» C. wattage rating
Discussion
191.

While putting three 1.5 V batteries into a flashlight, you put one in backwards. The flashlight will be ______________.

A. brighter than normal
B. dimmer than normal
C. off
D. the same
Answer» C. off
Discussion
192.

A string of resistors in a series circuit will:

A. divide the source voltage in proportion to their values
B. reduce the power to zero
C. cause the current to divide
D. increase the source voltage in proportion to the values
Answer» B. reduce the power to zero
Discussion
193.

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

A. 1
B.
Answer» B.
Discussion
194.

What is wrong, if anything, with this circuit?

A. R1 is open.
B. R1 is shorted.
C. R2 is open.
D. R2 is shorted.
Answer» C. R2 is open.
Discussion
195.

In the given circuit, R1 equals _____.

A. 100 k
B. 200 k
C. 300 k
D. More information is needed to find R1.
Answer» D. More information is needed to find R1.
Discussion
196.

As additional resistors are added to a series circuit, the total circuit resistance increases.

A. 1
B.
Answer» B.
Discussion
197.

How will an open resistor affect a series circuit?

A. Current will flow around the open resistor.
B. The open resistor will drop 0 V.
C. Total resistance will decrease.
D. No current will flow in the circuit.
Answer» E.
Discussion
198.

The total resistance is 35 .

A. 1
B.
Answer» B.
Discussion
199.

With a total resistance of 3300 ohms and a 45 V source, if R3 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
Discussion
200.

Which is a true statement about the circuit in the given circuit?

A. The batteries are series-aiding and the total source voltage equals 21 V.
B. The batteries are series-opposing and the total source voltage equals 3 V.
C. The batteries are series-aiding and the total source voltage equals 3 V.
D. The batteries are series-opposing and the total source voltage equals 21 V.
Answer» C. The batteries are series-aiding and the total source voltage equals 3 V.
Discussion