VIRGINIA (VA) ESC ELECTRONIC/COMMUNICATION SERVICE EXAM
1. What is the primary purpose of grounding in a communications
system?
A. Increase voltage
B. Reduce signal strength
C. Provide a safe path for fault current
D. Increase bandwidth
ANSWER : C
Explanation: Grounding protects equipment and personnel by providing
a low-resistance path for fault current.
2. Which cable is most commonly used for Ethernet networks?
A. Coaxial cable
B. Fiber optic cable
C. Twisted-pair cable
D. Ribbon cable
ANSWER : C
Explanation: Twisted-pair cable, such as Cat 5e and Cat 6, is the standard
medium for Ethernet installations.
,3. What does PoE stand for?
A. Power over Ethernet
B. Port of Ethernet
C. Power on Equipment
D. Port over Electronics
ANSWER : A
Explanation: PoE allows electrical power and data to be transmitted
through a single Ethernet cable.
4. Which device regenerates and retransmits signals in a network?
A. Router
B. Repeater
C. Switch
D. Gateway
ANSWER : B
Explanation: A repeater restores weakened signals to extend
communication distances.
5. Fiber optic cable transmits data using:
A. Electrical impulses
B. Magnetic fields
C. Light pulses
D. Radio waves
ANSWER : C
Explanation: Fiber optic cables use light pulses to transmit information
at high speeds.
6. What is the maximum horizontal distance for a standard Ethernet
run?
A. 50 feet
B. 100 meters
,C. 250 meters
D. 500 meters
ANSWER : B
Explanation: TIA/EIA standards limit horizontal cabling to 100 meters.
7. Which instrument is commonly used to test cable continuity?
A. Oscilloscope
B. Multimeter
C. Signal generator
D. Spectrum analyzer
ANSWER : B
Explanation: A multimeter checks continuity and resistance in
conductors.
8. A short circuit occurs when:
A. Resistance increases
B. Current takes an unintended low-resistance path
C. Voltage disappears
D. Frequency changes
ANSWER : B
Explanation: Short circuits allow excessive current flow through an
unintended path.
9. What does NEC stand for?
A. National Electrical Code
B. Network Engineering Code
C. National Electronic Council
D. Network Equipment Code
ANSWER : A
Explanation: The NEC establishes safety requirements for electrical
installations.
, 10. Which communication medium is immune to electromagnetic
interference?
A. Coaxial cable
B. Twisted-pair cable
C. Fiber optic cable
D. Telephone cable
ANSWER : C
Explanation: Fiber optic cables use light instead of electricity, making
them immune to EMI.
11. What is the function of a network switch?
A. Amplify signals
B. Route internet traffic between networks
C. Connect devices within a LAN
D. Convert analog signals
ANSWER : C
Explanation: Switches connect devices and direct traffic within local area
networks.
12. Which color pair is associated with pins 1 and 2 in T568B wiring?
A. Green pair
B. Blue pair
C. Orange pair
D. Brown pair
ANSWER : C
Explanation: T568B assigns the orange pair to pins 1 and 2.
13. Voltage is measured in:
A. Ohms
B. Watts
1. What is the primary purpose of grounding in a communications
system?
A. Increase voltage
B. Reduce signal strength
C. Provide a safe path for fault current
D. Increase bandwidth
ANSWER : C
Explanation: Grounding protects equipment and personnel by providing
a low-resistance path for fault current.
2. Which cable is most commonly used for Ethernet networks?
A. Coaxial cable
B. Fiber optic cable
C. Twisted-pair cable
D. Ribbon cable
ANSWER : C
Explanation: Twisted-pair cable, such as Cat 5e and Cat 6, is the standard
medium for Ethernet installations.
,3. What does PoE stand for?
A. Power over Ethernet
B. Port of Ethernet
C. Power on Equipment
D. Port over Electronics
ANSWER : A
Explanation: PoE allows electrical power and data to be transmitted
through a single Ethernet cable.
4. Which device regenerates and retransmits signals in a network?
A. Router
B. Repeater
C. Switch
D. Gateway
ANSWER : B
Explanation: A repeater restores weakened signals to extend
communication distances.
5. Fiber optic cable transmits data using:
A. Electrical impulses
B. Magnetic fields
C. Light pulses
D. Radio waves
ANSWER : C
Explanation: Fiber optic cables use light pulses to transmit information
at high speeds.
6. What is the maximum horizontal distance for a standard Ethernet
run?
A. 50 feet
B. 100 meters
,C. 250 meters
D. 500 meters
ANSWER : B
Explanation: TIA/EIA standards limit horizontal cabling to 100 meters.
7. Which instrument is commonly used to test cable continuity?
A. Oscilloscope
B. Multimeter
C. Signal generator
D. Spectrum analyzer
ANSWER : B
Explanation: A multimeter checks continuity and resistance in
conductors.
8. A short circuit occurs when:
A. Resistance increases
B. Current takes an unintended low-resistance path
C. Voltage disappears
D. Frequency changes
ANSWER : B
Explanation: Short circuits allow excessive current flow through an
unintended path.
9. What does NEC stand for?
A. National Electrical Code
B. Network Engineering Code
C. National Electronic Council
D. Network Equipment Code
ANSWER : A
Explanation: The NEC establishes safety requirements for electrical
installations.
, 10. Which communication medium is immune to electromagnetic
interference?
A. Coaxial cable
B. Twisted-pair cable
C. Fiber optic cable
D. Telephone cable
ANSWER : C
Explanation: Fiber optic cables use light instead of electricity, making
them immune to EMI.
11. What is the function of a network switch?
A. Amplify signals
B. Route internet traffic between networks
C. Connect devices within a LAN
D. Convert analog signals
ANSWER : C
Explanation: Switches connect devices and direct traffic within local area
networks.
12. Which color pair is associated with pins 1 and 2 in T568B wiring?
A. Green pair
B. Blue pair
C. Orange pair
D. Brown pair
ANSWER : C
Explanation: T568B assigns the orange pair to pins 1 and 2.
13. Voltage is measured in:
A. Ohms
B. Watts
