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1. In networking, what does attenuation refer to?
   a. Increase in signal strength
   b. Loss of signal strength
   c. Delay in data transmission
   d. Amplification of noise
   Answer: b.testbook
2. What is the standard unit for measuring signal loss in networking?
   a. Hertz
   b. Decibel
   c. Joule
   d. Meter
   Answer: b.sanfoundry+1
3. When a signal drops from 2000 watts to 1000 watts, what is the dB loss?
   a. 3
   b. 20
   c. 50
   d. 0
   Answer: a.studocu
4. What does a negative decibel value indicate in networking?
   a. Gain in signal
   b. Loss of signal
   c. No change in signal
   d. Increased noise
   Answer: b.careerride
5. The dB formula for comparing absolute power levels is:
   a. dB = P2 / P1
   b. dB = log10(P2 / P1)
   c. dB = 10 × log10(P2 / P1)
   d. dB = 20 × log10(P2 / P1)
   Answer: c.networkacademy+1
6. If a signal’s input power is 35 mW and output power is 0.0001393375 mW, what is the approximate decibel loss?
   a. -54 dB
   b. 54 dB
   c. 5.4 dB
   d. -5.4 dB
   Answer: a.networkacademy
7. What does an attenuation of 20 dB signify about the ratio of output to input power?
   a. Output is 10 times input
   b. Output is half input
   c. Output is 1/100th of input
   d. Output is equal to input
   Answer: c.scribd
8. Decibel loss makes calculations for gains and losses along a network path:
   a. More complex
   b. Additive and simple
   c. Multiplicative
   d. Impossible
   Answer: b.internetsociety
9. Acceptable dB loss per kilometer in single-mode fiber optic cable is typically:
   a. 0.01 dB/km
   b. 0.25 dB/km
   c. 1 dB/km
   d. 2 dB/km
   Answer: b.testbook+1
10. What does a 3 dB loss represent in terms of signal power?
    a. Signal reduced by 50%
    b. Signal doubled
    c. No change
    d. Signal reduced by 10%
    Answer: a.internetsociety+1
11. The decibel (dB) is best described as:
    a. An absolute unit of power
    b. A relative unit comparing two values
    c. A unit of frequency
    d. A measure of time
    Answer: b.sanfoundry+1
12. Which device can introduce additional dB loss in wired networking?
    a. Repeater
    b. Amplifier
    c. Cable
    d. Firewall
    Answer: c.testbook+1
13. What effect does a -10 dB loss have on a signal’s strength?
    a. Increases by 10 times
    b. Decreases by 10 times
    c. Doubles
    d. Triples
    Answer: b.magnusgulf
14. A splice in fiber optic cable typically introduces how much dB loss?
    a. 0.1 dB
    b. 1 dB
    c. 10 dB
    d. 0 dB
    Answer: a.lastmomenttuitions
15. The decibel loss over 100 km of fiber optic cable with 0.25 dB/km attenuation is:
    a. 25 dB
    b. 2.5 dB
    c. 0.25 dB
    d. 250 dB
    Answer: a.reddit+1
16. Which factor increases dB loss in copper cabling?
    a. Shorter cable length
    b. Lower temperature
    c. Higher frequency
    d. Better insulation
    Answer: c.testbook
17. If an attenuator adds 6 dB loss before an antenna, what is the return loss at the combined port if the antenna’s return loss is 10 dB?
    a. 22 dB
    b. 16 dB
    c. 10 dB
    d. 40 dB
    Answer: a.testbook
18. What is a common reference power in dBm calculations?
    a. 100 W
    b. 1 mW
    c. 10 mW
    d. 1 W
    Answer: b.tutorialspoint+1
19. Which dB loss may cause data transmission errors in a network?
    a. 0.1 dB
    b. 10 dB
    c. 0 dB
    d. 3 dB
    Answer: b.magnusgulf+1
20. Decibel loss is particularly critical in which network technology?
    a. Wireless LAN
    b. Bluetooth
    c. Fiber optics
    d. Infrared
    Answer: c.testbook+1
21. The mathematical expression for Signal-to-Noise Ratio (SNR) in dB is:
    a. SNR = Signal Power × Noise Power
    b. SNR = Signal Power − Noise Power
    c. SNR = 10 × log10(Signal Power / Noise Power)
    d. SNR = Noise Power − Signal Power
    Answer: c.testbook
22. In networking, what does a dB value of 0 indicate?
    a. No signal
    b. No loss or gain
    c. Maximum gain
    d. Minimum loss
    Answer: b.tutorialspoint+1
23. If received signal is measured as 5 dBm, this means:
    a. Power is 1 mW
    b. Power is 3.16 mW
    c. Power is 5 mW
    d. Power is 0.5 mW
    Answer: b.tutorialspoint
24. What is the advantage of using dB for loss calculations in networks?
    a. Complex math
    b. Additive calculations
    c. Multiplicative only
    d. Hard to interpret
    Answer: b.internetsociety
25. Signal loss due to connectors in fiber optics is approximately:
    a. 0.5 dB per connector
    b. 5 dB per connector
    c. 1 dB per connector
    d. 10 dB per connector
    Answer: a.lastmomenttuitions+1
26. The output power after a 20 dB loss with 100 mW input will be:
    a. 10 mW
    b. 1 mW
    c. 0.01 mW
    d. 100 mW
    Answer: b.scribd
27. Which formula is correct for dB loss calculation using milliwatts?
    a. dB = 10 × log10(Pout / Pin)
    b. dB = 20 × log10(Pout / Pin)
    c. dB = Pin / Pout
    d. dB = 2 × Pin × Pout
    Answer: a.networkacademy+1
28. What is the effect of doubling the cable length on dB loss?
    a. Loss stays same
    b. Loss halves
    c. Loss doubles
    d. Loss is zero
    Answer: c.testbook+1
29. For which factor is decibel loss not used?
    a. Power levels
    b. Signal distortion
    c. Voltage comparison
    d. Data compression
    Answer: d.sanfoundry
30. Decibel loss is considered additive. What happens when combining two segments of cable, each with 3 dB loss?
    a. Total loss is 6 dB
    b. Total loss is 3 dB
    c. Total gain is 6 dB
    d. Total loss is 9 dB
    Answer: a.internetsociety
31. Excess loss of a three-port coupler is:
    a. 0.2 dB
    b. 2 dB
    c. 20 dB
    d. 0.1 dB
    Answer: a.lastmomenttuitions
32. What does the decibel loss of -3 dB mean in terms of received power?
    a. Received power is twice the transmitted power
    b. Received power is half the transmitted power
    c. Received power equals transmitted power
    d. Received power is zero
    Answer: b.networkacademy
33. What is the symbol for decibel?
    a. dB
    b. Db
    c. db
    d. dBm
    Answer: a.sanfoundry
34. The loss of 10 dB in a fiber optic cable equates to output power being:
    a. Equal to input power
    b. 1/10th of input power
    c. 10 times the input power
    d. 100 times the input power
    Answer: b.magnusgulf
35. In a network with a loss of 20 dB, the power ratio is:
    a. 0.1
    b. 0.01
    c. 1
    d. 10
    Answer: b.scribd
36. A negative dB value means:
    a. Attenuation
    b. Amplification
    c. Zero signal
    d. No match
    Answer: a.careerride
37. Signal-to-noise ratio (SNR) in dB is important for:
    a. Measuring attenuation only
    b. Analyzing cable length
    c. Assessing data quality
    d. Calculating bandwidth
    Answer: c.testbook
38. Return loss measures:
    a. Signal sent vs. reflected
    b. Noise added
    c. Data compression
    d. Power gained only
    Answer: a.testbook
39. In networking links, why are dB losses preferred for calculation?
    a. Standardized measurement
    b. Easier math
    c. Universal units
    d. All the above
    Answer: d.internetsociety
40. SNR at input is 15 dB, output SNR is 10 dB. What is the network’s noise figure?
    a. 5 dB
    b. 25 dB
    c. 10 dB
    d. 1.5 dB
    Answer: a.testbook
41. A network has a measured loss of 30 dB. What is the output power if input was 100 mW?
    a. 1 mW
    b. 10 mW
    c. 0.1 mW
    d. 0.01 mW
    Answer: d.scribd+1
42. Which media experiences higher dB loss per distance?
    a. Fiber
    b. Copper
    c. Wireless
    d. All equally
    Answer: b.testbook
43. Decibel losses due to connectors and splices are considered:
    a. Fixed values per element
    b. Variable with power
    c. Unpredictable
    d. Irrelevant
    Answer: a.reddit
44. How does dB loss affect bandwidth?
    a. Decreases bandwidth
    b. Increases bandwidth
    c. No effect on bandwidth
    d. Doubles bandwidth
    Answer: a.testbook
45. What is considered excessive total dB loss in a typical enterprise fiber optic network run?
    a. Above 0.5 dB
    b. Above 3 dB
    c. Above 10 dB
    d. Above 30 dB
    Answer: b.reddit+1
46. Attenuation is most commonly measured in:
    a. Decibels per meter
    b. Decibels per kilometer
    c. Meters
    d. Watts
    Answer: b.testbook
47. What is the main advantage of expressing loss in dB for wireless links?
    a. Visual representation
    b. Easier calculation of total gain/loss
    c. Simplified connector selection
    d. Precise data format
    Answer: b.internetsociety
48. Which is a misconception regarding dB and dBm measurements?
    a. dB is for power ratios
    b. dBm is absolute power
    c. dB and dBm are interchangeable
    d. dBm references 1 mW
    Answer: c.magnusgulf
49. Suppose the input SNR is 25 dB, and output SNR after a 3 dB attenuator is 20 dB, what is the noise figure?
    a. 3 dB
    b. 5 dB
    c. 45 dB
    d. 20 dB
    Answer: a.testbook
50. Why is decibel loss critical for high-speed network installations?
    a. Ensures error-free communication
    b. Allows very long cable runs
    c. Minimizes latency
    d. Makes bandwidth unlimited
    Answer: a.magnusgulf+1

1. https://testbook.com/question-answer/loss-of-signal-power-as-light-travel-down-the-fibr–65a027b40f1016861daca8fb
2. https://www.sanfoundry.com/electronic-devices-circuits-questions-answers-decibel/
3. https://www.careerride.com/view/networking-test-questions-mcqs-15674.aspx
4. https://www.studocu.com/en-za/messages/question/13512372/if-a-signal-drops-from-2000-watts-to-1000-watts-there-will-be-a-db-lossa-3-b-20-c-50-d
5. https://www.networkacademy.io/ccna/wireless/understanding-amplitude-power-and-db
6. https://magnusgulf.com/db-vs-dbm-explained-for-fiber-optic-testing/
7. https://www.scribd.com/document/450993083/MCQ-in-Noise
8. https://www.internetsociety.org/wp-content/uploads/2017/10/dB-Math.pdf
9. https://testbook.com/question-answer/for-a-single-mode-optical-cable-with-0-25-dbkm-lo–60112f50ed706005c65cf033
10. https://www.reddit.com/r/networking/comments/qhns1r/question_on_acceptable_db_loss_with_sm_fiber_w/
11. https://lastmomenttuitions.com/optical-communication-mcqs/
12. https://testbook.com/objective-questions/mcq-on-noise-in-analog-communication-system–5eea6a0f39140f30f369e5fa
13. https://www.tutorialspoint.com/solutions-for-decibel-representation-problem-sets-of-wireless-communications
14. https://www.sanfoundry.com/avionics-questions-answers-gain-attenuation-decibels/
15. https://bcetodisha.ac.in/elearning/content/mca_uploads/2nd/Computer-Network-MCQ.pdf
16. https://www.allaboutcircuits.com/worksheets/decibel-measurements/
17. https://www.scribd.com/document/392231794/PROBLEMS-IN-DECIBELS
18. https://www.scribd.com/document/540140246/Quiz-1
19. https://testbook.com/question-answer/if-the-signal-power-10-db-m-and-noise-power-1–60ffc3c6bb8d40a2f8877c00
20. https://www.watelectronics.com/mcq/optical-fiber-communication/