AR FO Fiber Optics Contractor Exam
Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
1. What is the primary function of a fiber optic cable?
A. Conduct electricity
B. Transmit data as light
C. Provide structural support
D. Shield against electromagnetic interference
B. Transmit data as light
Rationale: Fiber optic cables transmit information using light
signals, which allows for high-speed and long-distance data
transmission with minimal signal loss.
2. Which type of fiber optic cable is most commonly used for long-
distance telecommunications?
A. Multimode
B. Single-mode
C. Plastic optical fiber
D. Step-index fiber
B. Single-mode
Rationale: Single-mode fibers have a small core that allows light to
travel straight, reducing dispersion and enabling long-distance
communication.
3. Which of the following is a key advantage of fiber optics over copper
cables?
A. Lower cost
B. Immunity to electromagnetic interference
C. Easy to splice
, D. Flexible bending radius
B. Immunity to electromagnetic interference
Rationale: Fiber optics are made of glass or plastic and do not
conduct electricity, making them immune to EMI, unlike copper
cables.
4. What is the typical core diameter of a single-mode fiber?
A. 50 µm
B. 62.5 µm
C. 9 µm
D. 100 µm
C. 9 µm
Rationale: Single-mode fiber has a core diameter of approximately 9
µm, which allows only one light mode to propagate, minimizing
dispersion.
5. Which type of fiber optic connector is widely used in
telecommunication networks?
A. RJ45
B. SC
C. USB
D. HDMI
B. SC
Rationale: SC (Subscriber Connector) is commonly used due to its
simple push-pull design, providing reliable connections in telecom
networks.
6. What does OTDR stand for in fiber optic testing?
A. Optical Time-Domain Reflectometer
B. Optical Transmission Data Receiver
C. Optical Total Data Relay
D. Optical Thermal Density Reader
A. Optical Time-Domain Reflectometer
Rationale: OTDR is used to test fiber optic cables by sending light
pulses and measuring reflections to locate faults or losses.
7. Which factor primarily causes attenuation in fiber optic cables?
A. Core diameter
B. Connector type
C. Absorption and scattering of light
D. Jacket color
, C. Absorption and scattering of light
Rationale: Light signals weaken in fiber optics due to absorption by
the material and scattering from impurities or irregularities.
8. What is modal dispersion?
A. Loss caused by bending fiber
B. Broadening of a light pulse due to multiple propagation paths
C. Light absorption in the fiber
D. Reflections at connectors
B. Broadening of a light pulse due to multiple propagation paths
Rationale: Modal dispersion occurs in multimode fibers because
different light modes travel at different speeds, causing signal
distortion.
9. Which color coding is commonly used for single-mode fibers in the
TIA/EIA-598 standard?
A. Orange
B. Yellow
C. Blue
D. Green
B. Yellow
Rationale: Yellow jackets identify single-mode fibers, while orange is
used for multimode fibers.
10. What is the function of a fiber optic patch panel?
A. Amplify light signals
B. Distribute and organize fiber connections
C. Convert optical signals to electrical
D. Protect fibers from moisture
B. Distribute and organize fiber connections
Rationale: Patch panels provide a central location to manage and
connect fiber optic cables efficiently.
11. What is the maximum recommended bending radius for a typical
single-mode fiber?
A. 5 mm
B. 10 mm
C. 30 mm
D. 50 mm
C. 30 mm
Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
1. What is the primary function of a fiber optic cable?
A. Conduct electricity
B. Transmit data as light
C. Provide structural support
D. Shield against electromagnetic interference
B. Transmit data as light
Rationale: Fiber optic cables transmit information using light
signals, which allows for high-speed and long-distance data
transmission with minimal signal loss.
2. Which type of fiber optic cable is most commonly used for long-
distance telecommunications?
A. Multimode
B. Single-mode
C. Plastic optical fiber
D. Step-index fiber
B. Single-mode
Rationale: Single-mode fibers have a small core that allows light to
travel straight, reducing dispersion and enabling long-distance
communication.
3. Which of the following is a key advantage of fiber optics over copper
cables?
A. Lower cost
B. Immunity to electromagnetic interference
C. Easy to splice
, D. Flexible bending radius
B. Immunity to electromagnetic interference
Rationale: Fiber optics are made of glass or plastic and do not
conduct electricity, making them immune to EMI, unlike copper
cables.
4. What is the typical core diameter of a single-mode fiber?
A. 50 µm
B. 62.5 µm
C. 9 µm
D. 100 µm
C. 9 µm
Rationale: Single-mode fiber has a core diameter of approximately 9
µm, which allows only one light mode to propagate, minimizing
dispersion.
5. Which type of fiber optic connector is widely used in
telecommunication networks?
A. RJ45
B. SC
C. USB
D. HDMI
B. SC
Rationale: SC (Subscriber Connector) is commonly used due to its
simple push-pull design, providing reliable connections in telecom
networks.
6. What does OTDR stand for in fiber optic testing?
A. Optical Time-Domain Reflectometer
B. Optical Transmission Data Receiver
C. Optical Total Data Relay
D. Optical Thermal Density Reader
A. Optical Time-Domain Reflectometer
Rationale: OTDR is used to test fiber optic cables by sending light
pulses and measuring reflections to locate faults or losses.
7. Which factor primarily causes attenuation in fiber optic cables?
A. Core diameter
B. Connector type
C. Absorption and scattering of light
D. Jacket color
, C. Absorption and scattering of light
Rationale: Light signals weaken in fiber optics due to absorption by
the material and scattering from impurities or irregularities.
8. What is modal dispersion?
A. Loss caused by bending fiber
B. Broadening of a light pulse due to multiple propagation paths
C. Light absorption in the fiber
D. Reflections at connectors
B. Broadening of a light pulse due to multiple propagation paths
Rationale: Modal dispersion occurs in multimode fibers because
different light modes travel at different speeds, causing signal
distortion.
9. Which color coding is commonly used for single-mode fibers in the
TIA/EIA-598 standard?
A. Orange
B. Yellow
C. Blue
D. Green
B. Yellow
Rationale: Yellow jackets identify single-mode fibers, while orange is
used for multimode fibers.
10. What is the function of a fiber optic patch panel?
A. Amplify light signals
B. Distribute and organize fiber connections
C. Convert optical signals to electrical
D. Protect fibers from moisture
B. Distribute and organize fiber connections
Rationale: Patch panels provide a central location to manage and
connect fiber optic cables efficiently.
11. What is the maximum recommended bending radius for a typical
single-mode fiber?
A. 5 mm
B. 10 mm
C. 30 mm
D. 50 mm
C. 30 mm
