Explore topic-wise MCQs in Electronics.

This section includes 54 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics knowledge and support exam preparation. Choose a topic below to get started.

1.

The period of a 10 kHz sine wave is 10 s.

A. True
B. False
Answer» C.
2.

The duty cycle of a square wave with a pulse width of 3 s and a period of 9 s is 40%.

A. True
B. False
Answer» C.
3.

What is the peak-to peak voltage of a 56 V ac voltage?

A. 158 V
B. 164 V
C. 82 V
D. 79 V
Answer» B. 164 V
4.

The average value of a sine wave is .707 times the peak value.

A. 1
B.
Answer» C.
5.

The period of a 10 kHz sine wave is 10 s.

A. 1
B.
Answer» C.
6.

A sawtooth voltage waveform has a linear ramp that changes voltage level with respect to time.

A. 1
B.
Answer» B.
7.

Which control should be moved to display more cycles of a signal on an oscilloscope?

A. horizontal position to left or right
B. volts/cm to a smaller number
C. vertical position to top or bottom
D. time/cm to a higher setting
Answer» E.
8.

What is the waveform period difference between the 60 Hz electricity used in this country and the 50 Hz used in Europe?

A. 3 ms
B. 16 ms
C. 4 ms
D. 20 ms
Answer» B. 16 ms
9.

A sine wave reaches maximum positive voltage at:

A. 90°
B. 0°
C. –90°
D. 360°
Answer» B. 0¬∞
10.

What is the peak-to-peak current value when an ammeter measures a 20 mA value?

A. 14 mA
B. 28 mA
C. 40 mA
D. 57 mA
Answer» E.
11.

The current is flowing in what direction?

A. clockwise
B. counterclockwise
C. in both directions at the same time
D. 50% of the time clockwise and 50% of the time counterclockwise
Answer» E.
12.

Test equipment selection enables the technician to both generate signals and:

A. change circuit conditions
B. inject signals
C. sense circuit conditions
D. change signal frequencies
Answer» D. change signal frequencies
13.

An ac wave shape could be a sine wave, square wave, or sawtooth wave.

A. 1
B.
C. 1
D.
Answer» B.
14.

What is the peak-to peak voltage of a 56 Vrms ac voltage?

A. 158 V
B. 164 V
C. 82 V
D. 79 V
Answer» B. 164 V
15.

DC current transfers better over longer distances than ac current.

A. 1
B.
Answer» C.
16.

Signal comparisons may be most easily seen when using which item of test equipment?

A. spectrum analyzer
B. multimeter
C. function generator
D. dual trace oscilloscope
Answer» E.
17.

How long would it take to transmit an electromagnetic wave to a receiving antenna 1,000 miles away?

A. 5.38 ms
B. 10.8 ms
C. 53.8 ms
D. 108 ms
Answer» B. 10.8 ms
18.

The __________ is defined as the ratio of a pulse width (positive or negative pulse or cycle) to the overall period of time of the wave.

A. pulse width
B. duty cycle
C. phase shift
D. active ratio
Answer» C. phase shift
19.

If a waveform period is determined to be 10 microseconds in duration, what is the frequency of the signal?

A. 100 Hz
B. 1000 Hz
C. 10 kHz
D. 100 kHz
Answer» E.
20.

A triangle wave consists of repeating:

A. positive ramps only
B. negative ramps only
C. positive and negative ramps of equal value
D. positive and negative ramps of unequal value
Answer» D. positive and negative ramps of unequal value
21.

The magnitude that an alternation varies from zero is called its:

A. altitude
B. amplitude
C. attitude
D. polarity
Answer» C. attitude
22.

One oscilloscope selector knob that allows the major and minor divisions of the graticule to be used to determine a waveform period is called a:

A. focus control
B. time/cm control
C. intensity control
D. volts/cm control
Answer» C. intensity control
23.

If a voltmeter measures a sine wave as 500 mV, what would be its average value?

A. 159.0 mV
B. 318.5 mV
C. 353.5 mV
D. 451.0 mV
Answer» E.
24.

What does the CRT oscilloscope display?

A. voltage and period
B. current and frequency
C. rms voltage and current
D. frequency and voltage
Answer» B. current and frequency
25.

A rectangular wave that has a duty cycle of 50 percent could be called a:

A. c wave
B. sawtooth wave
C. square wave
D. triangle wave
Answer» D. triangle wave
26.

The phase difference between sine waves of different frequencies is:

A. equal to their frequency differences
B. the difference in their fixed time displacement
C. the same throughout time
D. constantly changing
Answer» C. the same throughout time
27.

The duty cycle of a square wave with a pulse width of 3 s and a period of 9 s is 40%.

A. 1
B.
Answer» C.
28.

A test equipment item that has the ability to produce either square, triangular, or sawtooth waveforms is called:

A. a function generator
B. a radio frequency generator
C. an audio frequency generator
D. a frequency meter or counter
Answer» B. a radio frequency generator
29.

What term expresses the frequency of a rectangular wave?

A. Hz
B. period
C. PRF
D. PRT
Answer» D. PRT
30.

A square and a rectangular waveform appear to have a step voltage transition.

A. 1
B.
Answer» B.
31.

If a sine wave signal is 100 mV peak-to-peak, how many volts would be measured by a voltmeter?

A. 14.14 mV
B. 35.4 mV
C. 63.7 mV
D. 70.7 mV
Answer» C. 63.7 mV
32.

The rms value of a sine wave is .707 x peak-to-peak value/2.

A. 1
B.
Answer» B.
33.

What is the rms voltage value of an ac signal whose peak oscilloscope display uses 3 major divisions above the zero setting? (V/cm = 5)

A. 5.3 V
B. 10.6 V
C. 15.0 V
D. 21.2 V
Answer» C. 15.0 V
34.

If the frequency of a radio wave is increased, then its wavelength will:

A. increase
B. decrease
C. remain the same
D. cannot tell
Answer» C. remain the same
35.

A sine wave has:

A. four quadrants
B. two alternations
C. one period
D. all of the above
Answer» E.
36.

Why is ac current transfer more effective than dc current transfer over long distances?

A. due to the height of power lines
B. due to the use of ac generators
C. due to step-up and step-down transformers reducing I2R losses
D. due to very high voltages
Answer» D. due to very high voltages
37.

What is the name of a device used to directly measure the frequency of a periodic wave?

A. oscilloscope
B. frequency meter or counter
C. audio frequency generator
D. radio frequency generator
Answer» C. audio frequency generator
38.

One adjustable knob on the oscilloscope that allows the trace to be aligned with a reference graticule is called the:

A. position control
B. focus control
C. intensity control
D. volts/cm control
Answer» B. focus control
39.

What is the average value of a 12 V peak wave?

A. 3.82 V
B. 4.24 V
C. 7.64 V
D. 9.42 V
Answer» D. 9.42 V
40.

What is the period of a 16 MHz sine wave?

A. 196 ns
B. 62.5 ns
C. 31.25 ns
D. 19.9 ns
Answer» C. 31.25 ns
41.

The letter in the Greek alphabet used to represent wavelength is __________.

A. lambda
B. theta
C. omega
D. delta
Answer» B. theta
42.

Power companies supply ac, not dc, because:

A. it is easier to transmit ac
B. there is no longer a need for dc
C. dc is more dangerous
D. there are not enough batteries
Answer» B. there is no longer a need for dc
43.

What is the waveform period of a square wave signal that horizontally covers 3 major divisions per cycle? (time/cm = 50 ms)

A. 50 ms
B. 100 ms
C. 150 ms
D. 200 ms
Answer» D. 200 ms
44.

If current varies periodically from zero to a maximum, back to zero, and then repeats, the signal is:

A. direct
B. alternating
C. pulsating
D. repetitive
Answer» D. repetitive
45.

The distance that a signal's energy can travel in the time it takes for one cycle to occur is called the signal's:

A. amplitude
B. frequency
C. wavelength
D. period
Answer» D. period
46.

Which percentages of full-amplitude rise time are used for a pulse wave?

A. 0 to 50 percent
B. 0 to 100 percent
C. 5 to 95 percent
D. 10 to 90 percent
Answer» E.
47.

DC current flows in one direction, while ac current rises from zero to a maximum, then falls to zero in one direction, then rises to a maximum, then falls to zero in the opposite direction.

A. 1
B.
C. 1
D.
Answer» B.
48.

What is the name of a device that converts sound waves to electrical waves?

A. an amplifier
B. an antenna
C. a filter
D. a microphone
Answer» E.
49.

What is the peak value of a household appliance that uses a 230 V ac source?

A. 163 V
B. 230 V
C. 325 V
D. 480 V
Answer» D. 480 V
50.

The power that is distributed from a power plant to your home is:

A. high voltage to high voltage
B. low voltage to high voltage
C. high voltage to low voltage
D. low voltage to low voltage
Answer» D. low voltage to low voltage