Data Communication MCQs with Answers
Practice important Data Communication MCQs with answers and explanations.
Chapter: 45
Q601:
In Example 3.28, when adding decibel measurements, it shows the effect of _______ in the transmission.
A. attenuation and amplification
B. noise and interference
C. only signal gain
D. signal conversion to analog
Correct Answer:
A
Chapter: 46
Q602:
What unit is used to measure signal strength?
A. Watt
B. Volt
C. Decibel (dB)
D. Ampere
Correct Answer:
C
Chapter: 46
Q603:
When a signal is attenuated, the decibel value is _______.
A. Positive
B. Negative
C. Zero
D. Unchanged
Correct Answer:
B
Chapter: 46
Q604:
If the signal power is reduced to one-half, what is the attenuation in decibels?
A. +3 dB
B. −3 dB
C. 0 dB
D. −10 dB
Correct Answer:
B
Chapter: 46
Q605:
If the signal power is increased 10 times, the amplification in decibels is _______.
A. +3 dB
B. −3 dB
C. +10 dB
D. −10 dB
Correct Answer:
C
Chapter: 46
Q606:
The formula to calculate attenuation in decibels is _______.
A. dB = 10 log10 P
B. dB = 20 log10 P
C. dB = 10 log10 (P2/P1)
D. dB = P2 - P1
Correct Answer:
C
Chapter: 46
Q607:
What is the gain of a signal if its power is increased 10 times?
A. 3 dB
B. 10 dB
C. 1 dB
D. 100 dB
Correct Answer:
B
Chapter: 46
Q608:
The decibel value for a signal's amplification can be calculated as _______.
A. 10 log10 (P2/P1)
B. 10 log10 P
C. P2/P1
D. 20 log10 (P2/P1)
Correct Answer:
A
Chapter: 46
Q609:
If the signal's power is halved, the attenuation in decibels would be _______.
A. 0 dB
B. −3 dB
C. −6 dB
D. −10 dB
Correct Answer:
B
Chapter: 46
Q610:
In Example 3.26, the attenuation (loss of power) is calculated using the formula _______.
A. dB = 10 log10 (P2/P1)
B. dB = P2 / P1
C. dB = 20 log10 (P2 / P1)
D. dB = 10 log P1
Correct Answer:
A
Chapter: 46
Q611:
When a signal experiences amplification, the decibel value will be _______.
A. Negative
B. Positive
C. Zero
D. Unchanged
Correct Answer:
B
Chapter: 46
Q612:
The signal strength in decibels is usually calculated when the power is measured in _______.
A. Watts
B. Joules
C. Milliwatts (dBm)
D. Amperes
Correct Answer:
C
Chapter: 46
Q613:
In Example 3.27, when the signal power increases by 10 times, the amplification in dB is _______.
A. +3 dB
B. +10 dB
C. +20 dB
D. 0 dB
Correct Answer:
B
Chapter: 46
Q614:
If a signal’s power changes from P1 to P2 and the decibel value is calculated, it indicates the _______ between P1 and P2.
A. ratio
B. frequency
C. amplitude
D. phase
Correct Answer:
A
Chapter: 46
Q615:
The decibel (dB) scale is used for measuring _______ in a signal.
A. Resistance
B. Power change
C. Frequency change
D. Signal amplitude
Correct Answer:
B
Chapter: 46
Q616:
If the signal's power is reduced, the decibel value will be _______ and the attenuation will be _______.
A. Positive, Positive
B. Negative, Negative
C. Positive, Negative
D. Negative, Positive
Correct Answer:
D
Chapter: 47
Q617:
What does distortion in a signal refer to?
A. Change in signal frequency
B. Change in signal shape or form
C. Loss of signal power
D. Increase in signal intensity
Correct Answer:
B
Chapter: 47
Q618:
Distortion can occur in a composite signal made of _______.
A. A single frequency
B. Different frequencies
C. A pure tone
D. A high-frequency signal
Correct Answer:
B
Chapter: 47
Q619:
The cause of distortion is the _______ in propagation speed for each signal component.
A. Difference
B. Equality
C. Similarity
D. Invariance
Correct Answer:
A
Chapter: 47
Q620:
Differences in delay of signal components can create a difference in _______.
A. Voltage
B. Phase
C. Frequency
D. Amplitude
Correct Answer:
B