CO Communications Systems
Contractor Exam Questions And Correct
Answers (Verified Answers) Plus
Rationale2026 Q&A| Instant Download
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1. What is the primary purpose of a communications grounding system?
A. Reduce RF interference only
B. Improve transmission speed
C. Provide a low-impedance path to earth
D. Reduce cable attenuation
Answer: C
Rationale: Grounding ensures fault currents and surges travel safely to
earth, protecting equipment and personnel.
2. Category 6 cable is rated to support frequencies up to:
A. 100 MHz
B. 250 MHz
C. 350 MHz
D. 500 MHz
Answer: B
Rationale: Cat 6 cabling is specified for 250 MHz operation for Gigabit
Ethernet.
3. A communications backbone typically uses which type of cable?
A. Coaxial
B. Multi-mode or single-mode fiber
,C. Speaker wire
D. Alarm cable
Answer: B
Rationale: Fiber-optic cable is preferred for backbone due to bandwidth
and distance capability.
4. The maximum horizontal cable distance allowed by ANSI/TIA is:
A. 90 m
B. 100 m
C. 150 m
D. 200 m
Answer: A
Rationale: Standard allows 90 m of horizontal cabling plus 10 m for patch
cords.
5. What is the main advantage of PoE?
A. Faster data
B. VLAN compatibility
C. Allows power and data over one cable
D. Improves Wi-Fi coverage
Answer: C
Rationale: PoE delivers power through Ethernet pairs, eliminating separate
power runs.
6. A fiber-optic fusion splice typically results in:
A. High loss
B. Medium loss
C. Low loss
D. Variable loss
Answer: C
Rationale: Fusion splicing yields the lowest loss due to precise fiber
alignment.
7. RG-6 coaxial cable is primarily used for:
, A. Security alarms
B. CATV and satellite
C. Telephone systems
D. Voice paging
Answer: B
Rationale: RG-6 is standard for video distribution and satellite systems.
8. A demarcation point in a building separates:
A. Fire systems from security systems
B. Owner’s wiring from service provider’s wiring
C. Wi-Fi from wired networks
D. Public from private IP space
Answer: B
Rationale: The demarc marks where the carrier responsibility ends and
customer begins.
9. Which connector is most common for single-mode fiber?
A. BNC
B. ST
C. LC
D. F-type
Answer: C
Rationale: LC connectors are widely used due to small form factor.
10. What does OSP cabling refer to?
A. On-site perimeter cabling
B. Outside plant cabling
C. Operational safety procedures
D. Optical signal processing cabling
Answer: B
Rationale: OSP includes cables installed outdoors—underground, aerial,
or direct-burial.
Contractor Exam Questions And Correct
Answers (Verified Answers) Plus
Rationale2026 Q&A| Instant Download
1. What is the primary purpose of a communications grounding system?
A. Reduce RF interference only
B. Improve transmission speed
C. Provide a low-impedance path to earth
D. Reduce cable attenuation
Answer: C
Rationale: Grounding ensures fault currents and surges travel safely to
earth, protecting equipment and personnel.
2. Category 6 cable is rated to support frequencies up to:
A. 100 MHz
B. 250 MHz
C. 350 MHz
D. 500 MHz
Answer: B
Rationale: Cat 6 cabling is specified for 250 MHz operation for Gigabit
Ethernet.
3. A communications backbone typically uses which type of cable?
A. Coaxial
B. Multi-mode or single-mode fiber
,C. Speaker wire
D. Alarm cable
Answer: B
Rationale: Fiber-optic cable is preferred for backbone due to bandwidth
and distance capability.
4. The maximum horizontal cable distance allowed by ANSI/TIA is:
A. 90 m
B. 100 m
C. 150 m
D. 200 m
Answer: A
Rationale: Standard allows 90 m of horizontal cabling plus 10 m for patch
cords.
5. What is the main advantage of PoE?
A. Faster data
B. VLAN compatibility
C. Allows power and data over one cable
D. Improves Wi-Fi coverage
Answer: C
Rationale: PoE delivers power through Ethernet pairs, eliminating separate
power runs.
6. A fiber-optic fusion splice typically results in:
A. High loss
B. Medium loss
C. Low loss
D. Variable loss
Answer: C
Rationale: Fusion splicing yields the lowest loss due to precise fiber
alignment.
7. RG-6 coaxial cable is primarily used for:
, A. Security alarms
B. CATV and satellite
C. Telephone systems
D. Voice paging
Answer: B
Rationale: RG-6 is standard for video distribution and satellite systems.
8. A demarcation point in a building separates:
A. Fire systems from security systems
B. Owner’s wiring from service provider’s wiring
C. Wi-Fi from wired networks
D. Public from private IP space
Answer: B
Rationale: The demarc marks where the carrier responsibility ends and
customer begins.
9. Which connector is most common for single-mode fiber?
A. BNC
B. ST
C. LC
D. F-type
Answer: C
Rationale: LC connectors are widely used due to small form factor.
10. What does OSP cabling refer to?
A. On-site perimeter cabling
B. Outside plant cabling
C. Operational safety procedures
D. Optical signal processing cabling
Answer: B
Rationale: OSP includes cables installed outdoors—underground, aerial,
or direct-burial.
