Computer Systems (Year 10)

Question 1

Front: Define the terms ‘hardware’ and ‘software’.

Answer 1

Hardware: The physical components of a computer system (e.g., CPU, RAM, motherboard).

Software: The programs and operating information used by a computer (e.g., operating systems, applications).

Question 2

Distinguish between system software and application software

Answer 2

System Software: Includes the operating system and utility programs that manage computer hardware.

Application Software: Programs designed for end users (e.g., word processors, games, browsers).

Question 3

What are the roles of utility software

Answer 3

Maintains the computer system

(e.g., antivirus, backup software, disk defragmentation).

Question 4

What does antivirus software do

Answer 4

-> Detects, prevents, and removes malicious software (malware).

-> Scans files and applications for viruses and quarantines infected files.

-> Requires regular updates to stay effective against new threats.

Question 5

What is backup software and why is it important?

Answer 5

-> Creates copies of data to prevent data loss.

-> Can perform full backups (everything) or incremental backups (only changed files).

-> Used to restore data after hardware failure, accidental deletion, or cyberattacks

Question 6

What is disk defragmentation?

Answer 6

->Organises fragmented files on a hard drive to make them easier to access.

-> Helps the computer run faster by reducing the time needed to find and load files.

-> Not needed for SSDs, only for HDDs.

Question 7

What is fragmentation

Answer 7

-> When files are split into small pieces and stored in different locations on a hard drive.

-> Happens over time as files are created, deleted, and modified.

-> Slows down the computer because the hard drive takes longer to find and read the scattered data.

Question 8

What does compression software do?

Answer 8

Reduces file size to save storage space and improve transfer speeds.

Question 9

What is memory management

Answer 9

Allocates RAM to programs and manages virtual memory.

Question 10

What is user interface

Answer 10

Provides interaction between user and computer (GUI, CLI

Question 11

What is process management

Answer 11

Schedules tasks and manages CPU usage.

Question 12

What is file manage

Answer 12

Organizes and controls access to files

Question 13

What is peripheral managwmt

Answer 13

Controls devices like printers and keyboards

Question 14

What is the ALU

Answer 14

-> Performs arithmetic operations (addition, subtraction, multiplication, division).

-> Performs logical operations (AND, OR, NOT).

Works closely with the control unit and registers.

Question 15

What is the Control Unit (CU) used for?

Answer 15

-> Fetching, decoding, and executing instructions.

-> Controlling data flow between CPU, memory, and input/output devices.

-> Sending control signals to other components.

Question 16

What are registers in a CPU?

Answer 16

-> Small, high-speed storage locations inside the CPU used to store temporary data and instructions.

These are the instructions the CPU is actively using

Question 17

What is cache memory

Answer 17

-> A small, high-speed type of memory inside the CPU.
-> Stores frequently used instructions and data to speed up processing.
-> Faster than RAM but smaller in size

Question 18

How does cache memory improve CPU performance?

Answer 18

Reduces the time needed to access frequently used data.

Decreases reliance on slower RAM.

Helps the CPU process instructions faster, improving overall speed.

Question 19

Explain what is meant by an embedded system

Answer 19

A computer system built into a device to perform a specific function

(e.g., washing machines, microwaves, traffic lights).

Question 20

Explain the Von Neumann architecture.

Answer 20

A system where a single memory holds both data and instructions.

Uses registers to fetch, decode, and execute instructions.

Question 21

Describe the factors that affect CPU performance.

Answer 21

-> Clock speed
-> Number of cores
-> Cache size

Question 22

Describe the fetch-execute cycle.

Answer 22

Fetch: CU Retrieves instruction from memory. (Buses carry data to CPU)

Decode: CU Interprets the instruction and figures out what operation needs to be performed

Execute: CPU Carries out the instruction, using ALU for logic

Question 23

Define ‘main memory’

Answer 23

Main memory is the computer’s primary storage that holds data and instructions the CPU needs. It includes RAM and ROM.

Question 24

what is RAM

Answer 24

Temporary, volatile memory used to store active programs

Random access memory

Question 25

What is ROM

Answer 25

Permanent, non-volatile memory storing essential startup instructions ##footnote Read only memory

Question 26

Explain the need for secondary storage.

Answer 26

Used for long-term storage of files and data, as RAM is volatile.

Question 27

How does optical storage work?

Answer 27

Uses lasers to read and write data onto discs. The disc has a spiral track of tiny indents (pits) and flat areas (lands). A laser shines onto the disc: Lands reflect light → Read as 1 Pits scatter light → Read as 0

Question 28

How does solid-state storage work?

Answer 28

Uses flash memory (electronic circuits) to store data with no moving parts. Charge present = 1 No charge = 0

Question 29

Advantages kf solid state

Answer 29

Very fast (much faster than HDDs) Durable (no moving parts) Silent and energy-efficient

Question 30

Disadvantages of solid state

Answer 30

More expensive per GB than HDDs Limited write cycles (eventually wears out)

Question 31

How does magnetic storage work?

Answer 31

-> Uses magnetic fields to store data on spinning disks (platters). -> domains are either magnetised north or south -> north is read as 1 and south is read as 0 ##footnote Examples: Hard Disk Drives (HDDs), Magnetic Tape.

Question 32

Advantages kf magnetic storage

Answer 32

High capacity (several TBs) Cheaper per GB than SSDs Long lifespan if maintained properly

Question 33

Disadvantages kf magnetic storage

Answer 33

Slower than SSDs due to moving parts Fragile (can be damaged if dropped) Can be affected by external magnets

Question 34

Advantages of optical storage

Answer 34

Cheap to produce Portable Good for media distribution (movies, music, software

Question 35

Disadvantage of optical state

Answer 35

Low capacity compared to other storage types Slow read/write speeds Easily scratched or damaged

Question 36

Define cloud storage.

Answer 36

Storing data on remote servers accessed via the internet

Question 37

Explain the advantages of cloud storage.

Answer 37

Accessible anywhere, automatic backup, scalable.

Question 38

disadvantages of cloud storage

Answer 38

Requires internet, security concerns, ongoing costs.

Question 39

Construct and interpret truth tables for AND, OR, NOT, and XOR gates.

Answer 39

AND: Both inputs must be 1 to output 1. OR: At least one input must be 1 to output 1. NOT: Inverts input. XOR: Outputs 1 if inputs are different.

Question 40

Distinguish between high-level and low-level programming languages.

Answer 40

High-level: Easier to read, portable, but slower. Low-level: Faster, closer to machine code, harder to write.

Question 41

Distinguish between machine code and assembly language.

Answer 41

Machine Code: Binary instructions that the CPU executes directly Assembly: A human readable version of machine code that corresponds with CPU instructions (uses mnemonics)

Question 42

Explain the advantages and disadvantages of high- and low-level languages.

Answer 42

High-Level: Easy to use, but needs translation. Low-Level: Faster, more control, but harder to program.

Question 43

What are interpreters

Answer 43

Translates line-by-line, slower but easier to debug.

Question 44

What are compilers

Answer 44

Translates all at once, faster execution but harder debugging.

Question 45

What is an assembler

Answer 45

Converts assembly language into machine code.

Question 46

What is virtual memeory

Answer 46

When the computer runs out of space in RAM, it uses part of the SSD storage as extra memory to help keep the computer running smoothly

Question 47

How the fetch execute cycle work

Answer 47

Fetch The instructions are fetched to CPU from the primary memory (could be RAM) The fetched instruction is copied to one of the registers decode The instructions are decoded by the CU A value may be loaded into registers to prepare for execute stage execute The instructions are executed by different parts of the CPU such as ALU if the instruction is logical or other parts

Question 48

Rank three storage states from slowest to fastest

Answer 48

Slowest - optical Medium - Magnetic Fastest - solid

Question 49

Rank three storage states from lowest storage to most

Answer 49

Lowest - optical Medium - solid state Most - magnetic

Question 50

Rank three storage states from most durable to Least

Answer 50

Most - Solid State Drives (SSDs), Hard Disk Drives (HDDs), Least - Optical Storage (CDs/DVDs).

Question 51

What is system software

Answer 51

a type of computer program that manages and controls the computer hardware

Question 52

What is application software

Answer 52

computer programs designed for specific user tasks

Question 53

What five management’s does the operating system do

Answer 53

Memory management File management Process management Security management Peripheral management

Question 54

What is the CPU clock

Answer 54

The clock sends out regular electrical pulses that control the timing of all operations in the CPU. Each pulse allows the CPU to carry out a basic operation (like fetch or execute), meaning a higher clock speed, more instructions per second.

Question 55

What does more ticks in clock speed mean

Answer 55

Concert rate that ticks every time one cycle happens

Question 56

Benefits of embedded system

Answer 56

Smaller than non embedded systems - more compact devices Cheaper to produce - keep down cost of device More reliable than non embedded - last longer and need less maintenance use ROM - non embedded use RAM which is more expensive

Question 57

compare RAM and ROM in embedded and non embedded systems

Answer 57

Embedded Systems (use ROM): -> ROM is much cheaper than RAM, which helps keep the cost of the device down. -> Embedded systems have only one specific purpose, so there is no need for RAM; the instructions don’t have to change. -> ROM is non-volatile, which is good because the instructions are saved permanently. Non-Embedded Systems (use both ROM and RAM): -> ROM contains the essential startup instructions, is non-volatile, and cannot be changed or accessed by the user. -> RAM is volatile; the data stored in it changes depending on the tasks the user wants to do, because non embedded systems can carry out multiple different tasks and the in use origram needs to be stored somewhere where it will be deleted after the programs done running ->RAM is much more expensive, which generally makes non-embedded systems more expensive.

Question 58

What does increasing the number of cores do

Answer 58

Increases the number of instructions that can be carried out at the same time

Question 59

Benefits and limitations of virtual memory

Answer 59

Benefit = allows computer to multitask and open more applications at once that woukd not happen with just ram Limitation = secondary storage is much slower than the RAM, so there is noticeable lag when switching between applications or doing tasks that require memory retrieval

Question 60

Describe how CPU uses clock signal

Answer 60

Synchronises the different parts of the computer Determines when to carry out the instructions

Question 61

What do cores do

Answer 61

Carry out own fetch execute cycles