143 TEC FINAL EXAM
FALL 2003
Multiple Choice Questions Select the best answer
1. Ethernet uses the _____________ topology, where each physical port has a unique MAC address.
a. ring
b. star
c. bus
d. tree
e. hybrid
2. According to Hartley's law, the amount of information that can be transmitted in a given time is
directly proportional to channel _____________.
a. frequency
b. wavelength
c. transmission rate
d. bandwidth
e. range
3. CAT 5 is rated for an optimum data rate of __________.
a. 10 Mbps
b. 16 Mbps
c. 500 Mbps
d. 100 Mbps
e. 1000 Mbps
4. ______________ is a way of storing the same data on multiple hard disks.
a. UPS
b. CORBA
c. APS
d. RAID
e. ATM
5. An analog-to-digital conversion is accomplished by a(n) ____________.
a. IC
b. EBCDIC
c. ASCII
d. UART
e. modem
6. ________ is the exchange of predetermined signals when a connection is established between two
data devices and is not controlled by the operator.
a. Protocol converter
b. Handshaking
c. Interface
d. Network architecture
e. Processor
7. The term _________ is limited to the transmission of sound over wire or wireless.
a. telecommunication
b. radio
c. telephony
d. telex
e. None of the above
8. The ____________ layer handles network security, and data conversion, encryption and compression.
a. data link
b. transport
c. session
d. presentation
e. application
9.
As the AWG rating of a wire increases, its resistance ______ and its cmil area _____ .
a. increases, decreases
b. decreases, increases
c. decreases, decreases
d. increases, increases
e. stays the same, decreases
10. The Nyquist sampling theorem states that the optimum sampling rate is _________.
a. same as the maximum frequency
b. twice the maximum frequency
c. twice the minimum frequency
d. same as the minimum frequency
e. 10,000 samples per second
11. ____________ span all seven layers of the OSI model.
a. Routers
b. Switches
c. Repeaters
d. Bridges
e. Gateways
12. In a 100 BaseT designation, 100 refers to ________, Base refers to ___________, and T refers
to__________.
a. transmission speed, basic signaling, Thinnet
b. transmission speed, basic signaling, Thicknet
c. transmission speed, baseband signaling, Twisted pair
d. 100 meters, baseband signaling, Twisted pair
e. None of the above
13. ___________ noise is an equal mixture of noise of all frequencies.
a. Internal
b. External
c. Atmospheric
d. White
e. Excess or flicker
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14. The ______ is an error-detection-and-correction scheme designed for single bit errors.
a. Longitudinal Redundancy Check
b. Cyclic Redundancy Check
c. Hamming Code
d. Parity Check
e. Block Check Character
15. The __________ was a predetermined area that was used to govern who could carry calls in what
area.
a. POP
b. RBOC
c. LATA
d. ANI
e. PIC
16. If the characteristic impedance of a cable is 50 it must be terminated with a ______cable
terminator.
a. 100
b. 150
c. 50
d. high-power
e. hybrid
17. A ___________ network is built for exclusive use by a single organization.
a. circuit switching
b. message switching
c. public
d. private
e. virtual
18. The ________ data coding method is implemented in Ethernet and Token Ring LANs.
a. Manchester encoding
b. Protocol converter
c. Character code
d. Protocol interface
e. None of the above
19. ________ is the process in which two or more signals are combined for transmission over a single
communication path.
a. Multiplexing
b. Modulation
c. Switching
d. Sampling
e. Efficiency of transmission
20. The Intra-LATA transport is provided by the _____ and the Inter-LATA transport is provided by the
________.
a. LEC, IXC
b. IXC, LEC
c. LEC, LEC
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d. IXC, IXC
e. POP, POI
21. When certain symbols appear in the text more frequently than others, the __________ would be the
most appropriate data compression method.
a. 2 Binary 1 Quaternary
b. Run-length encoding
c. Manchester encoding
d. Huffman code
e. None of the above
22. ________ describes digital transmission of information.
a. Telecommunications
b. Data Communication
c. Graphic Communications
d. Telephony
e. Wireless Communications
23. The purpose of twists in a UTP is to ______________.
a. reduce crosstalk
b. reduce noise immunity
c. reduce impedance
d. All of the above
e. None of the above
24. The _________ is a noncontention-based system where response time is fairly predictable.
a. token passing
b. carrier sensing
c. multiple access
d. polling and selecting
e. collision detection
25. _________ can be described as the light gathering ability of an optical fiber.
a. Acceptance zone
b. Acceptance angle
c. Critical angle zone
d. Snell's law
e. Numerical aperture
26. In a _________ network, all computers are connected to central node.
a. ring
b. bus
c. tree
d. mesh
e. star
27. The Network Operating System resides on the ____________.
a. NDS
b. NIC
c. Server
d. Client
e. All of the above
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28. ________ refers to pulse broadening or spreading of light as it travels down the optical fiber.
a. Buffer
b. Numerical aperture
c. Dispersion
d. Scattering
e. Absorption
29. A client/server is an example of a ________ network.
a. cell switching
b. centralized
c. ring
d. private
e. distributed
30. A(n) _____________ provides for a connection between two layers, for example, Layer 2 to Layer
3.
a. Protocol converter
b. Handshaking
c. Interface
d. Network architecture
e. Processor
31. The _____________ initiates the retransmission of transmissions that have collided.
a. token passing
b. carrier sensing
c. multiple access
d. polling and selecting
e. collision detection
32. ___________ refers to simultaneous two-way transmission and is often described as a four-wire
transmission.
a. Simplex
b. Half-duplex
c. Full-duplex
d. Digital
e. Synchronous
33. _________ is a reflection that occurs when an electrical signal encounters an impedance irregularity.
a. Characteristic impedance
b. EMI
c. Crosswalk
d. Attenuation
e. Echo
34. ______ refers to a way of converting alphabets, numbers, and other special characters into a series of
0s and 1s.
a. Manchester encoding
b. Protocol converter
c. Character code
d. Protocol interface
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e. None of the above
35. A sound level of zero decibels corresponds to _____________________.
a. zero noise power
b. the smallest sound that can be heard
c. the noise figure for that system
d. the noise factor for that system
e. None of the above
36. _____________ allocates time-slots on a need-basis.
a. TDM
b. STDM
c. FDM
d. WDM
e. DWDM
37. ________ is the most commonly used method of coding digital signals transmitting and analog
signals digitally.
a. Pulse Amplitude Modulation
b. Pulse Position Modulation
c. Pulse Code Modulation
d. Pulse Width Modulation
e. Quadrature Amplitude Modulation
38. The ___________ is an independent U.S. government agency directly responsible to the Congress.
a. FCC
b. IEC
c. ANSI
d. ISO
e. USNC
39. When the angle of incidence is greater than the critical angle, there is _________.
a. refraction
b. total internal refraction
c. total internal reflection
d. propagation
e. both reflection or refraction
40. _____________ transmission is commonly referred to as a start-stop transmission.
a. Bandwidth
b. Broadband
c. Baseband
d. Asynchronous
e. Synchronous
41. ______ is used as a performance measure for analog systems and ______ is used as a performance
measure for digital systems.
a. SNR, BER
b. BER, SNR
c. Noise figure, SNR
d. BER, noise figure
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e. Noise, distortion
42. ________ refers to the amount of coupling between adjacent wire pairs.
a. Characteristic impedance
b. EMI
c. Crosstalk
d. Attenuation
e. Echo
43. __________ involves the simultaneous transmission of multiple channels over a single line.
a. Bandwidth
b. Broadband
c. Baseband
d. Asynchronous
e. Synchronous
44. ___________ operate at Layer 1 of the OSI model.
a. Routers
b. Switches
c. Repeaters
d. Bridges
e. Gateways
45. The _____________ layer implements the transmission protocol and provides for error control and
synchronization at the node-to-node basis.
a. physical
b. data link
c. network
d. transport
e. session
46. As the length of a cable increases, its ____________ decreases.
a. signal attenuation
b. signal strength
c. AWG number
d. resistance
e. none of the above
47. The ________ detects multiple errors within any length of message through the use of a unique
mathematical algorithm.
a. Longitudinal Redundancy Check
b. Cyclic Redundancy Check
c. Hamming Code
d. Parity Check
e. Block Check Character
48. The Network Interface Card and network drivers reside on the _________.
a. NDS
b. NIC
c. Server
d. Client
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e. All of the above
49. The ____layer sets up, coordinates and terminates conversations between the applications at each
end.
a. physical
b. data link
c. network
d. transport
e. session
50. Ethernet, Token Ring, and FDDI are all based on the ________ data link protocol.
a. SDLC
b. HDLC
c. ACDC
d. ISDN
e. ASCII
51. Satellite uses _________ waves to transmit data.
a. microwave
b. radio
c. sound
d. infrared
e. any or all of the above
52. An open implies __________ .
a. zero resistance
b. infinite resistance
c. infinite current
d. replacing the resistance with a wire
e. none of the above
53. Parity check is appropriate for checking ________ errors.
a. single-bit
b. two-bit
c. any number of bits
d. analog or digital
c. asynchronous
54. EMI is reduced by implementing the phenomenon where two waves equal in amplitude and
frequency, and ________ degrees out of phase, completely cancel one another.
a. 90
b. 0
c. 180
d. 270
e. 360
55. The light transmitted through a fiber is in the ______ region of the electromagnetic spectrum.
a. infrared
b. ultraviolet
c. cosmic
d. ultrasonic
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e. microwave
56. To connect a voltmeter to measure voltage across a resistor _____________.
a. open the circuit at a point and use the meter to complete the circuit.
b. open the circuit at the positive and negative terminals of the voltage source.
c. allow the circuit to remain as is and connect the meter across the resistor.
d. short-circuit the resistance to be checked and connect the meter across it.
e. open the circuit at one point and connect the meter to one end.
57. To connect an ammeter to measure current _________.
a. open the circuit at a point and use the meter to complete the circuit.
b. open the circuit at two points and connect the meter across both points.
c. allow the circuit to remain as is and connect the meter across the resistance.
d. short-circuit the resistance to be checked and connect the meter across it.
e. open the circuit at one point and connect the meter to one end.
58. When light is incident on an interface, it is either ___________ or ____________
a. transmitted, refracted
b. reflected, refracted
c. reversed, forwarded
d. reflected internally, reflected externally
e. none of the above
59. The peak voltage is 20 volts. How much is the average voltage for the full wave?
a. 14.14 V
b. 12.74 V
c. 6.37 V
d. none of the above
60. The peak to peak voltage is 10 volts. How much is the rms voltage?
a. 6.37 V
b. 5 V
c. 7.07 V
d. none of the above
61. If two identical wire conductors are tied in series, their total resistance is _____.
a. double the resistance of one wire
b. one-half the resistance of one wire
c. the same as the resistance of one wire
d. none of the above
62. Calculate the maximum voltage drop a 5k ohm W resistor can handle safely.
a. 18.8 V
b. 25 V
c. 12.8 V
d. 15.8 V
e. none of the above
63. The conductance of a copper wire is 50 Siemens. What is its resistance?
a. 50 Ohms
b. 20 m Ohms
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c. 200 m Ohms
d. 2 m Ohms
e. 5 Ohms
64. In a step-down transformer, the output voltage is ________ the input voltage.
a. less than
b. more than
c. equal to
d. double
e. none of the above
65. In a step-up transformer, if the turns ratio is 4:1, and the input voltage is 25 volts, the output voltage
is:
a. 100 volts
b. 400 volts
c. 25 volts
d. 6.25 volts
e. none of the above
A
-
+
R1
-
R3
+
R2
+
C
B
-
66. In the above figure, meter A measures _________________________.
a. current
b. voltage
c. resistance
d. resistance or voltage
e. current or voltage
67. In the above figure, meter B measures _________________________.
a. current
b. voltage
c. resistance
d. resistance or voltage
e. current or voltage
68. In the above figure, meter C measures _________________________.
a. current
b. voltage
c. resistance
d. resistance or voltage
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e. current or voltage
69. Calculate the current in a series circuit that has three 100 ohm resistors connected to a 10 volt power
supply.
a. 33 mA
b. 0.033 mA
c. 10 mA
d. 0.1 A
e. None of the above
70. Calculate the current in the first resistor in a parallel circuit that has three 100 ohm resistors
connected to a 10 volt power supply.
a. 33 mA
b. 0.033 mA
c. 10 mA
d. 0.1 A
e. None of the above
71. Calculate the efficiency of an asynchronous transmission of 746 ASCII (8-bit code) characters with
two start bits, one stop bit, and one error-detection character.
a. 67%
b. 91%
c. 92%
d. 86%
e. none of the above
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