*** means i chose that answer..
Question 1 of 25
_________ cable consists of an inner copper core and a second conducting outer sheath.
Fiber-optic
Shielded twisted pair
Coaxial***
Unshielded twisted pair
Question 2 of 25
What is the symbol rate (baud rate) of a binary system if 12 kbits are transmitted in 8 seconds?
1500 baud***
1000 baud
2000 baud
2500 baud
Question 3 of 25
In _________ transmission, characters are sent one at a time and each character are framed with a start bit and a stop bit.
Asynchronous***
Synchronous
Parallel
Duplex
Question 4 of 25
Electrical coupling between nearby cables results in transmission impairment called ___________.
attenuation
impulse noise
Crosstalk***
propagation delay
Question 5 of 25
A composite signal is decomposed into three sine waves with frequencies of 100 Hz, 220 Hz, and 2.1 kHz. What is the bandwidth of the composite signal?
100 Hz
2 kHz***
0.5 kHz
200 Hz
Question 6 of 25
Digital Transmission is better than Analog Transmission because ___________ .
Use of repeaters instead of amplifiers increases the noise
analog data has better security and privacy
Channel can be better utilized since it is easier to implement multiplexing with digital techniques***
Large Scale Integration of Digital Circuitry increases the cost
Question 7 of 25
_________ is a type of transmission impairment in which the signal loses strength during transmission through a communication media.
Impulse noise
Crosstalk
Attenuation***
Propagation delay
Question 8 of 25
The ASCII code of character ‘s’ is _________.
11100010
1110011***
1100011
11000010
Question 9 of 25
In _________ transmission, characters are grouped together as a data frame and transmitted as a whole without start and stop bits and without gaps between characters.
Duplex
Synchronous***
Asynchronous
Parallel
Question 10 of 25
Which category of the UTP cable has the best quality?
Category 4 UTP
Category 2 UTP
Category 3 UTP
Category 5 UTP***
Question 11 of 25
In a time–domain plot, the horizontal axis measures the _________, and the vertical axis measures the _________.
Time, frequency
Frequency, phase
Time, phase
Time, amplitude***
Question 12 of 25
Radio waves are an example of communication through _________.
A refractive medium
A non-metallic medium
An unguided medium***
A guided medium
Question 13 of 25
In a frequency–domain plot, the horizontal axis measures the _________, and the vertical axis measures the _________.
Frequency, peak amplitude***
Frequency, phase
Time, frequency
Time, amplitude
Question 14 of 25
_________ cable consists of two insulated copper wires arranged in a regular spiral pattern.
Thick Coaxial
Fiber-optic
Thin Coaxial
Twisted pair***
Question 15 of 25
What is the percentage of overhead for transimitting a 7-bit code using 2 stop bit and 1 parity bit ?
22%.
30%.***
36%.
40%.
Question 16 of 25
The _________ field in a data frame in Synchronous Transmission is a unique bit pattern to signify the end of a frame.
error check
control
preamble
Postamble***
Question 17 of 25
If the bit rate of a signal is 2000 bps, how many bits can be sent in 10 ms?
20 bits***
2 bits
10 bits
1 bit
Question 18 of 25
A binary system is using a noise free channel with bandwidth of 1000 Hz, What is the expected channel capacity?
1000 bps
2000 bps***
4000 bps
3000 bps
Question 19 of 25
_________ is a 7-bit code to convert text data into binary format.
Huffman code
Manchester code
ASCII code***
Da Vinci code
Question 20 of 25
_________ cable are composed of a glass or plastic inner core surrounded by cladding, all encased in an outside jacket.
Shielded twisted pair
Unshielded twisted pair
Fiber-optic***
Coaxial
Question 21 of 25
Twisted pair cables can use _________ connectors to plug into computer network card.
BNC
RJ45***
RJ8
RJ11
Question 22 of 25
Given a channel with bandwidth of 1 MHz, and the Signal to noise (S/N) ratio of 20 dB, what is the channel capacity?
About 50 Mbps
About 6 Mbps***
About 2 Mbps
About 20 Mbps
Question 23 of 25
The two major classes of transmission media are _________.
Determinate and indeterminate
Fixed and unfixed
Metallic and non-metallic
Guided and unguided***
Question 24 of 25
What is the symbol rate (baud rate) of a four-level system if 12 kbits are transmitted in 8 seconds?
750 baud***
500 baud
1250 baud
1000 baud
Question 25 of 25
200,000 bits are sent in 10 seconds. What is the bit rate of the system?
2 kbps
100 bps
20 kbps***
200 bps
