Physical Layer Concepts: A Comprehensive Guide for Computer Networks

Question 1

What is the primary purpose of employing a twisted pair cable as a transmission medium?

Accepted Answer

To minimize electromagnetic interference

Answer

To enhance signal strength

Answer

To facilitate high data transmission rates

Answer

To ensure flexibility and ease of installation

Question 2

Which type of fiber optic cable features a single glass core enveloped by cladding?

Accepted Answer

Single-mode fiber

Answer

Multi-mode fiber

Answer

Graded-index fiber

Answer

Step-index fiber

Question 3

What distinguishes synchronous transmission from asynchronous transmission?

Accepted Answer

Synchronous transmission employs a clock to synchronize data transfer, while asynchronous transmission does not.

Answer

Asynchronous transmission uses a clock to synchronize data transfer, while synchronous transmission does not.

Answer

Synchronous transmission offers faster speeds than asynchronous transmission.

Answer

Asynchronous transmission provides greater reliability compared to synchronous transmission.

Question 4

What is the primary function of a network interface card (NIC)?

Accepted Answer

Providing a physical interface for data transmission

Answer

Connecting a computer to a network

Answer

Managing network traffic

Answer

Encrypting data before transmission

Question 5

What is the role of a repeater in a network?

Accepted Answer

Regenerating and amplifying signals

Answer

Filtering out noise and interference

Answer

Switching data between different networks

Answer

Providing encryption for secure data transmission

Question 6

What is the main goal of the Institute of Electrical and Electronics Engineers (IEEE) 802.3 standard?

Accepted Answer

Defining the physical layer and MAC layer protocols for Ethernet networks

Answer

Establishing security standards for wireless communication

Answer

Specifying the routing protocols used in the Internet

Answer

Developing standards for optical fiber communication

Question 7

Which of the following is an unguided transmission medium?

Accepted Answer

Microwave

Answer

Coaxial cable

Answer

Fiber optic cable

Question 8

Which physical layer standard specifies a wired Ethernet network that operates at 10 gigabits per second using fiber optic cables?

Accepted Answer

10 Gigabit Ethernet

Answer

Ethernet 10Base-T

Answer

Fast Ethernet

Answer

Gigabit Ethernet

Question 9

Which component is NOT part of the Physical Layer in computer networks?

Accepted Answer

Internet Protocol (IP)

Answer

Transmission Media

Answer

Network Interface Card

Answer

Signal Encoding

Question 10

Which transmission medium is best suited for transmitting signals over long distances without the need for repeaters?

Accepted Answer

Fiber Optic Cable

Answer

Twisted Pair Cable

Answer

Coaxial Cable

Answer

Wireless Medium

Question 11

Which signal encoding technique represents binary data by varying the amplitude of the signal?

Accepted Answer

Amplitude Modulation (AM)

Answer

Frequency Modulation (FM)

Answer

Phase Modulation (PM)

Answer

Quadrature Amplitude Modulation (QAM)

Question 12

Which type of connector is commonly used to connect twisted pair cables to network devices?

Accepted Answer

RJ-45

Answer

RJ-11

Answer

BNC

Answer

F-connector

Question 13

What is the primary function of a modem in a computer network?

Accepted Answer

To convert digital signals into analog signals for transmission over telephone lines

Answer

To amplify signals over long distances

Answer

To filter out noise from the transmission medium

Answer

To establish logical connections between devices

Question 14

What is the main purpose of the Physical Layer in a computer network?

Accepted Answer

To provide a reliable transmission channel for data

Answer

To establish and maintain network connections

Answer

To manage the flow of data between devices

Answer

To provide security to the network

Question 15

What is the key difference between baseband and broadband transmission?

Accepted Answer

Broadband uses higher frequencies than baseband

Answer

Baseband uses digital signals, while broadband uses analog signals

Answer

Baseband is used for short distances, while broadband is used for long distances

Answer

Baseband transmits data in parallel, while broadband transmits data in serial

Question 16

Which of the following factors does NOT affect the performance of a transmission medium?

Accepted Answer

Cost

Answer

Bandwidth

Answer

Signal-to-noise ratio

Answer

Latency

Question 17

Which of the following is NOT considered a component of the Physical Layer in computer networks?

Accepted Answer

Physical layer protocols

Answer

Transmission media

Answer

Signal encoding

Answer

Network interface cards

Question 18

What is the primary function of transmission media in computer networks?

Accepted Answer

To provide a physical path for data transmission

Answer

To encode data into electrical signals

Answer

To manage data flow and ensure reliable transmission

Answer

To amplify and regenerate network signals

Question 19

Which type of transmission medium exhibits the highest signal quality in terms of bandwidth and immunity to interference?

Accepted Answer

Fiber-optic cable

Answer

Twisted-pair cable

Answer

Coaxial cable

Answer

Wireless transmission

Question 20

What is the primary purpose of signal encoding in the Physical Layer?

Accepted Answer

To convert digital data into a form suitable for transmission over physical media

Answer

To compress data for more efficient transmission

Answer

To encrypt data for secure communication

Answer

To detect and correct errors in transmitted data

Question 21

What is the function of a network interface card (NIC) in the Physical Layer?

Accepted Answer

To provide a physical connection between a device and the network

Answer

To manage data flow and ensure reliable transmission

Answer

To perform signal encoding and decoding

Answer

To route data packets to their intended destinations

Question 22

What is the primary purpose of using repeaters in a computer network?

Accepted Answer

To amplify and regenerate weakened signals

Answer

To extend the reach of network signals

Answer

To filter out unwanted noise and interference

Answer

To convert data from one signal encoding format to another

Question 23

Within the scope of computer networks, what is the primary responsibility of the Physical Layer?

Accepted Answer

Transmitting data signals over physical media, like cables or wireless channels

Answer

Encapsulating data into frames suitable for network transmission

Answer

Establishing and maintaining logical connections between network devices

Answer

Providing routing and forwarding functionality to guide data packets through the network

Question 24

Which transmission medium offers the optimal combination of high bandwidth and minimal latency?

Accepted Answer

Fiber optic cable utilizing light pulses

Answer

Twisted pair copper cabling

Answer

Coaxial cable with a solid copper core

Answer

Wireless transmission using radio waves

Question 25

What is the primary purpose of modulation in the context of signal encoding?

Accepted Answer

Converting digital data signals into analog signals suitable for transmission over physical media

Answer

Increasing the bandwidth of the signal to accommodate more data

Answer

Reducing signal distortion and improving signal quality during transmission

Answer

Enhancing signal security by encrypting the data before transmission

Question 26

Which of the following transmission media types requires a physical connection between transmitting and receiving devices?

Accepted Answer

Twisted pair copper cabling with insulated wires

Answer

Microwave transmission utilizing high-frequency radio waves

Answer

Infrared transmission using light waves within a limited range

Answer

Satellite transmission utilizing communication satellites in space

Question 27

In the context of a 100Base-T Ethernet network, what is the maximum theoretical data transmission rate?

Accepted Answer

100 megabits per second (Mbps)

Answer

10 megabits per second (Mbps)

Answer

1 gigabit per second (Gbps)

Answer

10 gigabits per second (Gbps)

Question 28

Which factors collectively influence the data transmission rate achievable on a network?

Accepted Answer

All of the above factors combined

Answer

The type of transmission medium used for data transfer

Answer

The signal encoding technique employed to represent data

Answer

The modulation scheme utilized to convert digital signals for transmission

Question 29

What is the primary function of repeaters in a network infrastructure?

Accepted Answer

Regenerating and amplifying signals to extend their reach and overcome signal degradation

Answer

Connecting different network segments to facilitate data exchange

Answer

Providing error correction mechanisms to ensure data integrity during transmission

Answer

Handling routing and switching functions to direct data packets along optimal paths

Question 30

Within the OSI networking model, what is the primary responsibility of the Data Link Layer?

Accepted Answer

Providing error control mechanisms to ensure reliable data transmission

Answer

Establishing and maintaining logical connections between network devices

Answer

Routing data packets across the network based on their destination addresses

Answer

Providing encryption and decryption services to protect data during transmission

Question 31

What Physical Layer component manages data flow and access to the shared transmission medium, preventing collisions?

Accepted Answer

Media Access Control (MAC)

Answer

Network Interface Card (NIC)

Answer

Transceiver

Answer

Physical Layer Protocol

Question 32

Which of the following is NOT a key milestone in the evolution of Physical Layer standards for computer networks?

Accepted Answer

Invention of the telephone

Answer

Introduction of fiber optics

Answer

Development of Ethernet

Answer

Standardization of Wi-Fi

Question 33

When it comes to susceptibility to interference, which of the following transmission media is the most vulnerable?

Accepted Answer

Unshielded twisted-pair (UTP) cable

Answer

Coaxial cable

Answer

Fiber optic cable

Question 34

What is the term for the process of converting digital signals into analog signals for transmission?

Accepted Answer

Modulation

Answer

Demodulation

Answer

Multiplexing

Answer

Encoding

Question 35

In the context of the Physical Layer, what is the primary function of error detection and correction mechanisms?

Accepted Answer

To ensure reliability in data transmission by detecting and correcting errors that may arise during transmission.

Answer

To enhance the speed of data transfer

Question 36

In the Physical Layer, what is the main purpose of using shielded cables?

Accepted Answer

To minimize electromagnetic interference (EMI)

Answer

To increase the data transfer rate

Answer

To reduce the cost of cable installation

Answer

To enhance physical protection

Question 37

What is the primary role of a repeater in the Physical Layer of a network?

Accepted Answer

To amplify and regenerate signals, extending the reach of a network

Answer

To provide encryption for secure data transmission

Answer

To filter out noise and interference

Question 38

Which of the following is NOT a component of the Physical Layer in computer networks?

Accepted Answer

Routing Protocol

Answer

Transmission Media

Answer

Repeaters

Answer

Network Interface Card

Question 39

Which type of transmission media transmits data as electromagnetic waves, enabling wireless network connectivity?

Accepted Answer

Wireless

Answer

Twisted Pair

Answer

Fiber Optic

Answer

Coaxial Cable

Question 40

Which signal encoding technique utilizes a combination of voltage levels to represent data, ensuring synchronization between sender and receiver?

Accepted Answer

Manchester Encoding

Answer

NRZ-I

Answer

NRZ-L

Question 41

What is the primary purpose of repeaters in the Physical Layer?

Accepted Answer

To amplify and regenerate signals over long distances, extending the reach of network connections

Answer

To convert signals into different formats

Answer

To connect different network segments

Question 42

Which type of connector is commonly used for fiber optic cables, facilitating secure and efficient data transmission?

Accepted Answer

SC

Answer

RJ-45

Answer

DB-9

Answer

BNC

Question 43

Explain the key difference between baseband and broadband transmission in computer networks.

Accepted Answer

Baseband utilizes the entire channel bandwidth for a single signal, while broadband divides the bandwidth into multiple channels, allowing simultaneous transmission of multiple signals.

Answer

Baseband is faster than broadband.

Question 44

Which of the following physical topologies involves connecting all devices in a circular fashion, passing data in a single direction?

Accepted Answer

Ring

Answer

Mesh

Answer

Bus

Answer

Star

Question 45

What is the primary advantage of using shielded twisted pair cabling in network installations?

Accepted Answer

It minimizes electromagnetic interference, ensuring reliable data transmission in noisy environments.

Answer

To simplify installation

Answer

To provide greater flexibility

Answer

To increase data transmission speed

Question 46

Which industry-standard protocol defines the specifications for the Physical Layer in Ethernet networks?

Accepted Answer

IEEE 802.3

Answer

TCP/IP

Answer

SMTP

Answer

HTTP

Question 47

What is the core function of a network interface card (NIC) in the Physical Layer?

Accepted Answer

To provide a physical connection between a host computer and a network, enabling data transmission and reception.

Answer

To store and forward data

Answer

To provide a user interface for network management

Answer

To encrypt and decrypt data

Question 48

What is the primary responsibility of the Physical Layer in a computer network?

Accepted Answer

Transmitting and receiving data signals over a physical medium.

Answer

Managing the flow of data packets within the network.

Answer

Providing logical addresses to network devices.

Answer

Ensuring secure data transmission through encryption.

Question 49

Which transmission medium is most suitable for long-distance, high-speed data transfer?

Accepted Answer

Optical fiber

Answer

Twisted-pair cable

Answer

Radio waves

Answer

Coaxial cable

Question 50

What is the main purpose of signal encoding in the Physical Layer?

Accepted Answer

Converting digital data into a format suitable for transmission over a specific medium.

Answer

Securing data through encryption.

Answer

Compressing data to reduce transmission time.

Answer

Detecting and correcting errors during data transmission.

Question 51

Which of the following is a common signal encoding technique used in the Physical Layer?

Accepted Answer

Manchester encoding

Answer

Huffman encoding

Answer

Arithmetic encoding

Answer

Run-length encoding

Question 52

How does the Physical Layer contribute to maintaining network connectivity?

Accepted Answer

It transmits and receives data packets across the physical medium, ensuring communication between devices.

Answer

It routes data packets to their destination addresses.

Answer

It manages network traffic to prevent congestion.

Answer

It provides security measures to protect data from unauthorized access.

Question 53

What is a crucial design consideration for the Physical Layer?

Accepted Answer

Matching the transmission medium to the appropriate signal encoding technique.

Answer

Prioritizing speed over reliability in data transmission.

Answer

Maximizing the cost of network infrastructure.

Answer

Minimizing the number of devices connected to the network.

Question 54

What is the primary function of a physical connector in a network?

Accepted Answer

Providing a physical connection between two devices or network components.

Answer

Controlling the flow of data packets within the network.

Answer

Converting data from digital to analog format.

Answer

Amplifying the strength of signal transmissions.

Question 55

What distinguishes coaxial cable from other transmission media?

Accepted Answer

It consists of a central conductor surrounded by an insulating layer and a braided shield.

Answer

It uses radio waves to transmit data over long distances.

Answer

It is composed of twisted pairs of wires to reduce interference.

Answer

It is the most common type of transmission medium used in modern networks.

Question 56

What is the fundamental difference between guided and unguided transmission media?

Accepted Answer

Guided media rely on physical pathways like cables, while unguided media use wireless signals.

Answer

Unguided media are always faster than guided media.

Answer

Guided media are more susceptible to interference than unguided media.

Answer

Guided media are more expensive to install than unguided media.

Question 57

What is a significant advantage of using fiber optic cables?

Accepted Answer

They offer high bandwidth capacity and low signal loss, enabling long-distance data transmission with minimal degradation.

Answer

They are significantly cheaper than other types of transmission media.

Answer

They are highly susceptible to electromagnetic interference.

Answer

They are easy to install and maintain compared to other cable types.