State the uses of 3D printers
State four data types used in MS Excel
State two data protection rules that should be obeyed by all staff in a hospital.
Describe the difference between a barcode and A quick Response code (QR code)
State the name of the storage space used by the operating system when there is insufficient RAM
Describe a typical situation that requires the use of:
(i) a high-level language
(ii) a low-level language.
High level languages are used in situations when:
Low level languages are used in situations when:
Describe what is meant by shareware.
the trial version of software for a limited time/number of uses with limited features free of charge
If a full version is required need to pay a fee/sign up
When the trial is over user is asked to pay/sign up
Protected by copyright
Type of software licence
State Advantages of online booking
State the reasons for system review and maintenance
451/1
COMPUTER STUDIES
PAPER 1
THEORY
DECEMBER 2021
TIME: 2 HOURS
FORM TWO END OF TERM TWO 2O21 EXAM
451/1
COMPUTER STUDIES
PAPER 1
THEORY
TIME: 2½ HOURS
INSTRUCTIONS TO CANDIDATES:
What is the difference between a logical file and a physical file?
Outline any 2 Examples of wireless transmission media (2marks)
Jane has noticed the following problems with her computer (2mks)
State three possible causes of these problems and how they can be solved (3mks)
There could be several possible causes for the issues Jane is experiencing with her computer keyboard, including:
1. Software Issues
- Cause: Outdated or corrupt system files, drivers, or operating system.
- Solution:
- Ensure the operating system and drivers are up-to-date.
- Run a system file checker to repair any corrupted system files (e.g., on Windows, run "sfc /scannow" from the Command Prompt).
- Consider reinstalling the operating system if issues persist.
2. Hardware Issues:
- Cause: Physical damage or malfunction in the keyboard hardware.
- Solution:
- Check for physical damage or debris under the keys and clean the keyboard if necessary.
- If cleaning doesn't help, consider replacing the keyboard with a new one.
3. Resource Overload:
- Cause: The computer may be running too many background processes or lacking sufficient hardware resources.
- Solution:
- Close unnecessary background applications and processes to free up system resources.
- Consider upgrading the computer's RAM, CPU, or storage if it's outdated and unable to handle current software demands.
- Use task manager or activity monitor to identify and terminate resource-intensive processes.
4. Malware or Viruses:
- Cause: Malicious software can slow down a computer, cause hanging, and delay startup.
- Solution:
- Perform a full system scan using reputable antivirus or anti-malware software to remove any threats.
- Ensure that the operating system's security patches are up-to-date.
5. Disk Fragmentation:
- Cause: Fragmented files can slow down the loading of applications and overall system performance.
- Solution:
- Run a disk defragmentation tool (e.g., Windows' built-in tool) to optimize file storage on the hard drive.
- Consider upgrading to a solid-state drive (SSD) for faster application loading times.
6. Insufficient Storage:
- Cause: If the hard drive is nearly full, it can cause slow performance.
- Solution:
- Free up space by deleting unnecessary files and programs.
- Consider upgrading to a larger capacity hard drive or SSD if storage space remains an issue.
7. Background Processes and Startup Items:
- Cause: Too many unnecessary programs running in the background or starting up with the computer.
- Solution:
- Disable or remove unnecessary startup items and background processes to improve startup time.
- Use the Task Manager or System Preferences (on macOS) to manage startup items.
It's important to diagnose the specific cause of the issues Jane is facing by troubleshooting each potential problem one by one. In some cases, a combination of these solutions may be necessary to fully resolve the problems with her computer keyboard.
Identify which processor in the PC systems below is likely to process instructions more efficiently. Justify your answer.
Differentiate between uploading and downloading a file
Uploading a file refers to the process of transferring a file from a local computer to a remote webserver while downloading a file refers to the process of transferring or copying a file from a remote webserver to a local machine
The website has a uniform resource locator (URL).
An example of a URL is given.
https://www.google.co.ke/index.html
Complete the table to identify the name of each section of the URL.
https : protocol
google.co.ke: domain name
/index.html: webpage/file name
State the factors that affect the performance of the CPU
Number of cores
The number of cores a processor has directly affects the performance of the processor. Each core can perform its own fetch-execute cycle independently of others, so different applications can be allocated to different cores. Quad-core (four-core) and even octa-core (eight-core) processors are becoming common
Cache memory
A processor’s cache is a small portion of incredibly fast memory. It has read and write speeds far higher than hard disk drives and even SSDs. The cache is used to store frequently used information and reduces time wasted in fetching the same information from main memory time and time again
Clock speed
A processor’s clock speed relates to the frequency of the pulses generated by the system clock. The higher the frequency, the more cycles of the fetch-execute cycle can be completed in the same period of time.
Word length
A word is a group of bits that is treated as a single unit by a processor. Words can be used for representing both instructions and data. The length of a word is the number of bits that are assigned to it, with higher word lengths allowing for more bits to be transferred and manipulated as a single unit.
Address bus width
The width of a bus relates to the number wires that make up the bus. Increasing the width of the address bus increases the range of addresses that it can specify, hence increasing the computer’s amount of addressable memory. Adding a single wire doubles the number of addressable memory locations
Data bus width
Increasing the width of the data bus increases the volume of data that can be transferred over the bus at any one time. A wider data bus allows the processor to fetch more data from the main memory in one cycle of the fetch-execute cycle, reducing the number of cycles required to fetch large volumes of data.
List three types of errors that are likely to exist in a program (3 marks)
Syntax errors-Incorrect use of programming language
Logical errors- The program do not give the expected output
Runtime errors- Premature end of a program
Define Domain integrity
Domain integrity - ensures that all data in a field contain valid values
Why must operating system be installed in a computer before any other program