Explore topic-wise MCQs in Electronics.

This section includes 217 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics knowledge and support exam preparation. Choose a topic below to get started.

101.

A voltmeter is connected across the current path.

A. True
B. False
Answer» B. False
102.

An ammeter is connected across the current path.

A. True
B. False
Answer» C.
103.

When the current is 2.5 A, how many coulombs pass a point in 0.2 s?

A. 12.5 C
B. 1.25 C
C. 0.5 C
D. 5 C
Answer» D. 5 C
104.

Current flows in a circuit when

A. A switch is opened
B. A switch is closed
C. The switch is either open or closed
D. There is no voltage
Answer» C. The switch is either open or closed
105.

Eighttenths coulomb passes a point in 4 s. The current in amperes is

A. 1.6 A
B. 16 A
C. 2 A
D. 0.2 A
Answer» E.
106.

The unit of electrical charge is the

A. Coulomb
B. Joule
C. Volt
D. Watt
Answer» B. Joule
107.

A 20 kHz pulse waveform consists of pulses that are 15 µs wide. The duty cycle

A. Is 1%
B. Is 30%
C. Is 100%
D. Cannot be determined
Answer» C. Is 100%
108.

Duty cycle is the characteristic of a pulse waveform that indicates the high time versus the low time.

A. True
B. False
Answer» C.
109.

How many degrees are there in p/3 rad?

A.
B. 60°
C. 180°
D. 27°
Answer» C. 180°
110.

The unit of frequency is the hertz.

A. True
B. False
Answer» B. False
111.

The angular position of a phasor represents the angle of the sine wave with respect to a reference.

A. True
B. False
Answer» B. False
112.

If the rms voltage drop across a 15 kΩ resistor is 16 V, the peak current through the resistor is

A. 15 mA
B. 1.5 mA
C. 10 mA
D. 1 mA
Answer» C. 10 mA
113.

The duty cycle of a pulse waveform with a pulse width of 10 µs and a period of 100 µs is 25%.

A. True
B. False
Answer» C.
114.

One sine wave has a positive-going zero crossing at 15° and another sine wave has a positive-going zero crossing at 55°. The phase angle between the two waveforms is

A.
B. 45°
C. 40°
D. None of the above
Answer» D. None of the above
115.

The length of a phasor represents the amplitude.

A. True
B. False
Answer» B. False
116.

A pulse waveform has a high time of 8 ms and a pulse width of 32 ms. The duty cycle is

A. 25%
B. 50%
C. 1%
D. 100%
Answer» B. 50%
117.

If the rms current through a 4.7 kΩ resistor is 4 mA, the peak voltage drop across the resistor is

A. 4 V
B. 18.8 V
C. 26.6 V
D. 2.66 V
Answer» D. 2.66 V
118.

If the rms current through a 6.8 kΩ resistor is 8 mA, the rms voltage drop across the resistor is

A. 5.44 V
B. 54.4 V
C. 7.07 V
D. 8 V
Answer» C. 7.07 V
119.

The average value of a 12 V peak sine wave over one complete cycle is

A. 0 V
B. 1.27 V
C. 7.64 V
D. 6.37 V
Answer» B. 1.27 V
120.

A saw-tooth wave has a period of 10 ms. Its frequency is

A. 10 Hz
B. 50 Hz
C. 100 Hz
D. 1,000 Hz
Answer» D. 1,000 Hz
121.

The designation rms means repetitions measured per second.

A. True
B. False
Answer» C.
122.

Periodic is characterized by a repetition at fixed time intervals.

A. True
B. False
Answer» B. False
123.

A square wave has a period of 60 µs. The first odd harmonic is

A. 5 kHz
B. 50 kHz
C. 500 kHz
D. 33.33 kHz
Answer» C. 500 kHz
124.

Average value of a sine wave is 0.707 times the peak value.

A. True
B. False
Answer» C.
125.

A sine wave with an rms value of 12 V is riding on a dc level of 18 V. The maximum value of the resulting waveform is

A. 6 V
B. 30 V
C. 35 V
D. 0 V
Answer» D. 0 V
126.

The conductive loop on the rotor of a simple two-pole, single-phase generator rotates at a rate of 400 rps. The frequency of the induced output voltage is

A. 40 Hz
B. 100 Hz
C. 400 Hz
D. Indeterminable
Answer» D. Indeterminable
127.

If the peak of a sine wave is 13 V, the peak-to-peak value is

A. 6.5 V
B. 13 V
C. 26 V
D. None of the above
Answer» D. None of the above
128.

A sinusoidal current has an rms value of 14 mA. The peak-to-peak value is

A. 45.12 mA
B. 16 mA
C. 39.6 mA
D. 22.6 mA
Answer» D. 22.6 mA
129.

A signal with a 400 µs period has a frequency of

A. 250 Hz
B. 2,500 Hz
C. 25,000 Hz
D. 400 Hz
Answer» C. 25,000 Hz
130.

The instantaneous value is the voltage or current value of a waveform at its peak.

A. True
B. False
Answer» C.
131.

A sine wave with a period of 4 ms is changing at a faster rate than a sine wave with a period of

A. 0.0045 s
B. 2 ms
C. 1.5 ms
D. 3,000 µs
Answer» B. 2 ms
132.

A 1 kHz signal has a period of 1 ms.

A. True
B. False
Answer» B. False
133.

Two series resistors are connected to an ac source. If there are 7.5 V rms across one resistor and 4.2 V rms across the other, the peak source voltage is

A. 16.54 V
B. 1.65 V
C. 10.60 V
D. 5.93 V
Answer» B. 1.65 V
134.

A waveform has a baseline of 3 V, a duty cycle of 20%, and an amplitude of 8 V. The average voltage value is

A. 4 V
B. 4.6 V
C. 1.6 V
D. 11 V
Answer» B. 4.6 V
135.

A phasor represents

A. The magnitude and a quantity direction
B. The width of a quantity
C. The phase angle
D. The magnitude of a quantity
Answer» B. The width of a quantity
136.

If a sine wave goes through 10 cycles in 20 µs, the period is

A. 20 µs
B. 4 µs
C. 2 µs
D. 100 µs
Answer» D. 100 µs
137.

When a sine wave has a frequency of 100 Hz in 12 s it goes through

A. 1/100 cycle
B. 12 cycles
C. 120 cycles
D. 1,200 cycles
Answer» E.
138.

A sine wave of 15 kHz is changing at a faster rate than a sine wave with a frequency of

A. 25 kHz
B. 12 kHz
C. 18 kHz
D. 1.3 MHz
Answer» C. 18 kHz
139.

The average half-cycle value of a sine wave with a 40 V peak is

A. 25.48 V
B. 6.37 V
C. 14.14 V
D. 50.96 V
Answer» B. 6.37 V
140.

Amplitude is the maximum value of a voltage or current.

A. True
B. False
Answer» B. False
141.

A ramp is the type of waveform characterized by a non-linear increase or decrease in voltage or current.

A. True
B. False
Answer» C.
142.

Sine wave A has a positive-going zero crossing at 45°. Sine wave B has a positive-going zero crossing at 60°. Which of the following statements is true?

A. Wave A leads wave B by 15°
B. Wave A lags wave B by 15°
C. Wave A leads wave B by 105°
D. Wave A lags wave B by 105°
Answer» B. Wave A lags wave B by 15°
143.

To produce an 800 Hz sine wave, a four-pole generator must be operated at

A. 200 rps
B. 400 rps
C. 800 rps
D. 1,600 rps
Answer» C. 800 rps
144.

An atom of a semiconductor has _______________ electrons in the valence shell.

A. 4
B. 8
C. 2
D. 0
Answer» B. 8
145.

The ___ represents a negative charge in an atom.

A. electron
B. proton
C. neutron
D. None of the above
Answer» B. proton
146.

The symbol that represents electrical charge is Q.

A. 1
B.
Answer» B.
147.

A ___ resistor has color bands of yellow, violet, yellow, gold.

A. 470 5%
B. 5.7 M 5%
C. 37 k 5%
D. 470 k 5%
Answer» E.
148.

Switches are used to open and close paths for current.

A. 1
B.
Answer» B.
149.

The ___ is placed in series with the flow of current.

A. voltmeter
B. ammeter
C. ohmmeter
D. wattmeter
Answer» C. ohmmeter
150.

A resistor color coded with brown, black, and orange bands has a value of 10 k.

A. 1
B.
Answer» B.