admin@kcseforecast.com

Q&A-KCSE Computer Studies Paper 1

Factors to consider when choosing DTP software. (4 marks)

  1. Availability in the market
  2. Initial and maintenance cost
  3. User friendliness
  4. Compatibility
  5. User needs

One characteristic of a robot is its mechanical structure.
State two other characteristics of a robot

  • It has electrical components.
  • It is programmable.

 

Question Image

(a)Explain why programmers prefer to represent instruction in hexadecimal rather than in binary

  • A larger number of values can be represented using fewer characters.
  • the shorter length and more characters make the pattern easier to read and understand
  • recognisable character codes can be used for debugging

(b) Give two other uses of hexadecimal

  • HMTL color codes representing RGB spectrum in the web development
  • representation of MAC and IP addresses allowing a larger combination of unique addresses

(a)Explain why programmers prefer to represent instruction in hexadecimal rather than in binary

  • A larger number of values can be represented using fewer characters.
  • the shorter length and more characters make the pattern easier to read and understand
  • recognisable character codes can be used for debugging

(b) Give two other uses of hexadecimal

  • HMTL color codes representing RGB spectrum in the web development
  • representation of MAC and IP addresses allowing a larger combination of unique addresses
Question Image

Describe the input, processing and output from a computerised traffic-control system.

input

  • from sensors
  • from camera images [Max 2]

processing

  • analyse data from sensors
  • calculate average traffic flow/speed
  • send signals to adjust change lights/timing

output

  • change lights at the junction
  • change timing plan
Question Image

Differentiate between bus topology and star topology of networks. What are the advantages and disadvantages of star topology over bus topology

  • Bus topology is characterised by common transmission media shared by all the connected nodes
  • Star topology is characterised by a central switching node connected directly to each of the multiple nodes in the network

Advantages of Star topology over Bus topology

  • Faster communication as compared to bus topology
  • Independent line of connection allows freedom of removing or adding nodes

Disadvantages of Star topology over Bus topology

  • Expensive as compared to the bus topology
  • Long cable length
Question Image

Explain the difference between main memory and secondary storage.

  • Main memory is transitory/temporary/volatile, secondary storage is (semi-)permanent
  • The processor can only use data/instructions that are in the main memory
  • Main memory is directly accessible to the processor, secondary storage is not directly accessible to the processor 
Question Image

State and explain characteristics of an algorithm

Input : An algorithm can take 0 or more inputs well defined outputs

Finiteness: an algorithm must terminate in finite time and after finite number of steps. 

Definiteness : an algorithm must be clear and unambiguous. Each and every step of an algorithm must be clear and precise and it must have only one meaning

Feasibility: should be feasible with the available resources

 

Output : must produce at least one well defined output

Independent : should have a step-by-step directions which is independent of any programming language

Correctness: should solve the problem it is designed to solve

Efficiency: must take the shortest time possible to run and should require the least memory space. It should use a minimum number of computation steps and memory to produce the desired  output. takes little time and memory to run

Generality: should not be limited to a specific case. It should work for all the valid inputs. works for many possible inputs

Effectiveness : should statements that are relevant to the problem. Every step must be basic and essential. 

 

Question Image

There are security concerns associated with cloud storage.
(a) State one way in which providers of cloud storage could prevent security breaches by their own employees

 (b) Explain why data on networks is encrypted

(a) One from:

  • Background checks
  • Access control
  • Physical security
  • User policies

(b) To prevent unauthorised access (1) so that data remains confidential (1) by making it unintelligible (1) because it is scrambled (1)

Question Image

Explain why the organization's management and the analyst need to work together to define the problem accurately during system development

  • College authorities are the experts in the problem
  • A system Analyst is an expert with computers
  • The two need to pool resources to come up with a clear definition
  • Agree on the outcomes so that when the system is , there are a set of criteria to judge it by
Question Image

A computer laboratory experiences power supply problems. Describe three power related problems that should be addressed

Blackout: This is unexpected discontinuation of power supply in the laboratory.

Power sag: Sudden drop of voltage levels that lasts less than a second.

Transients/ surge: High voltage flowing.

Brownout: Partial blackout where there's low voltage flow.

Question Image

1 (a) Computer networks are valuable to many businesses and individuals.
(i) State the purpose of network protocols

Any one of:
To allow connected machines to communicate
To provide the rules of communication between two networked devices

Question Image

Explain two computer hardware features that may be considered when selecting a laptop computer to be used in developing a KCSE computer studies project (4mks)

Multimedia Capability - A laptop with strong multimedia capabilities is essential for a computer studies project submitted on CD-RW. This ensures that the laptop can efficiently handle multimedia content, providing a seamless experience in creating and presenting project materials.

Processor Speed - Opting for a laptop with a high processor speed is crucial. This feature enables the smooth execution of multiple applications simultaneously, enhancing overall project efficiency and reducing processing delays.

Hard Disk Capacity - Consider a laptop with ample hard disk capacity, as the Microsoft Office suite used in computer projects requires significant space for the installation and storage of project files. A spacious hard drive ensures that there is sufficient room for data and applications.

Main Memory Capacity - Given that students often work with multiple programs concurrently during a project, it's important to choose a laptop with an adequate main memory size. A smaller main memory may result in performance issues, hindering the seamless operation of various software applications during project development.