| Question Bank accompanying Business Data Communications |
Chapter 2 – Physical Layer

Signaling is _____. the transmission path over which information propagates wiring cables between locations combining multiple signals for transmission over one medium converting data to signals for transmission over physical media * Answer: (d)
A signal is _____. information added to data to remove errors cables connecting networked locations detectable transmitted energy that can be used to carry information converting data to signals for transmission over physical media * Answer: (c)
The only layer in the TCP/ IP stack that deals with the limitations of nature is _____. the data link layer the physical layer the network layer the transport layer * Answer: (b)
Signals in copper wire are transmitted as _____. sound signals light signals electrical signals. smoke signals * Answer: (c)
A physical medium is _____. the transmission path over which a signal propagates the method of combining multiple signals for transmission over one medium used to convert data to signals for transmission detectable transmitted energy that can be used to carry information * Answer: (a)
As a physical medium, copper possesses all of the following properties except _____. copper is relatively abundant copper is a good conductor of electricity copper is relatively inexpensive copper can transmit information over very long distances * Answer: (d)
The term UTP stands for _____. unshielded telephone pair unshielded twisted pair uncovered twisted pair uncovered telephone pair * Answer: (b)
A CAT 5 cable has _____ wires.
4
6
8
10 * Answer: (c)
A CAT 5 cable is terminated using connectors called _____.
RJ 11 connectors
RJ 19 connectors
RJ 45 connectors
RJ 54 connectors * Answer: (c)
As a physical medium, optical fiber possesses all of the following properties except _____. it is relatively light in weight it can carry signals for long distances without the need for repeaters it is relatively inexpensive it is as robust as copper in withstanding abuse * Answer: (d)
Single mode fiber is preferred over multi-mode fiber for short distances.
True
False * Answer: (b)
Data is converted to signals for transmission because _____. data is expensive to transport over physical media there is no known method to transport data over physical media signals are inexpensive to transport over physical media network carriers prefer to transport signals * Answer: (b)
Good signals have all the following properties except _____. good signals do not need to be multiplexed good signals are efficient at using bandwidth good signals are resistant to noise good signals are easy to detect at the receiver’s end * Answer: (a)
The figure shows an example of _____. digital data transmitted using a digital signal digital data transmitted using an analog signal analog data transmitted using a digital signal analog data transmitted using an analog signal * Answer: (b)
Amplitude is a measure of _____. the height of a sine wave the number of cycles made by a sine wave in one second the position of a sine wave at the start time
None of the above * Answer: (a)
Modulation is the process of _____. spinning a wheel to generate a sine wave increasing the amplitude of a sine wave increasing the frequency of a sine wave changing one or more properties of a sine wave in response to data * Answer: (d)
Quadrature amplitude modulation _____. is another name for amplitude modulation combines amplitude modulation with phase modulation combines amplitude modulation with frequency modulation
None of the above * Answer: (b)
Binary signals are preferred over other forms of signals (ternary, decimal etc) because _____. binary signals are the easiest to detect reliably by the receiver binary signals can carry the most amount of information in a given time period binary signals are the fastest known means of transmitting data binary signals are the easiest to generate for the sender * Answer: (a)
A bit _____. transforms elements from one set of elements to another set generates sine waves for transmission over a medium is the unit of information that designates one of two possible states changes one or more properties of a sine wave in response to data * Answer: (c)
Coding is _____. the unit of information the transformation of elements from one set of elements to another set the generation of sine waves for transmission over a medium changing one or more properties of a sine wave in response to data * Answer: (b)
Noise is _____. the transformation of elements from one set of elements to another set the generation of sine waves for transmission over a medium changing one or more properties of a sine wave in response to data any disturbance that interferes with the normal operation of a device * Answer: (d)
The ASCII code is used to encode _____. characters in the English alphabet characters in the Chinese language characters in all languages characters in most languages spoken around the world * Answer: (a)
Unicode is used to encode _____. characters in the English alphabet only characters in the Chinese language only characters in most languages characters in the 5 most common languages spoken around the world * Answer: (c)
In FDM _____. signals from each channel are sent at a specified frequency signals from each channel are sent at a specified amplitude signals from each channel are sent at a specified phase signals from each channel are sent at a specified time * Answer: (a)
In TDM _____. signals from each channel are sent at a specified frequency signals from each channel are sent at a specified amplitude signals from each channel are sent at a specified phase signals from each channel are sent at a specified time * Answer: (d)