I.T

Question 1

Functions of ALU, control unit, RAM and ROM

Answer 1

ALU- arithmetic logical unit as the brain of the computer handles all the calculations and logical operations.

Control unit- as the manager of the computer directs the flow of data and instructions within the computer’s memory and ensuring that tasks are carried out efficiently.

RAM- this is like the workspace of the computer providing temporary storage for data and instructions that the computer is currently using.

ROM- this is like the library of the computer storing essential instructions and data that remain even when the computer is off.

Question 2

What is data communication

Answer 2

The transmission of data (raw facts, concepts or instructions) location to the other in order to enable communication (create a shared understanding) between locations.

Question 3

What is telecommunication

Answer 3

The process of exchanging data or information from one location to another electronically

Question 4

What is bandwidth

Answer 4

The amount of data that can be transmitted through the channel each second

Question 5

What are the categories of bandwidth

Answer 5

Narrow band-Data is transmitted at a slow speed example telegraphed transmission

Voice band- Telephone lines are used, allowing data to be transmitted at a rate of up to 800 characters per second.

Broad band-Broad-band uses fiber-optic cables, microwave and satellite transmission to allow very fast transmission of data

Question 6

What is simplex

Answer 6

Data can be transmitted in only one direction. Examples are radio and TV

Question 7

What is half duplex

Answer 7

Data can be transmitted in both direction, but not at the same time. Examples are CB radio and walkie-talkie

Question 8

What is full duplex

Answer 8

Data can be transmitted in both direction at the same time. Examples are telephones, mobile phones and sending data via the internet.

Question 9

What is communication media

Answer 9

Communication media (or transmission media) are the storage and transmission tools used to store and deliver information or data.

Question 10

Types f communication media

Answer 10

Wired
Wireless

Question 11

What are the types of networks

Answer 11

LAN- Local Area Network is a computer network that interconnects computers within a limited area such as a home, school, laboratory or office building.

WAN- Wide Area Network is a computer network in which the computers connected may be far apart, even in different countries.

MAN- A metropolitan area network is a computer network in a geographical area or region larger than that of a LAN.

Question 12

What are type of transmission media

Answer 12

Twisted pairs- These are pairs of copper wires that have been twisted together to transmit data, for example, telephone wire

Coaxial cable- This consists of a single copper wire surrounded by at least three layers

Fiber optic cable- This is a cable made up of dozens or hundreds of thin strands of glass or plastic that use light to transmit signals.

Question 13

Types of long distance transmission media

Answer 13

1. Microwave
2. Satellite
3. Infrared
4. Bluetooth
5. Wi-Fi

Question 14

What is network topology

Answer 14

This relates to how the computers are physically connected within the network.

Question 15

Types of network topology

Answer 15

Star Topology
⚫ This is a topology where all the devices must connect to a central concentrator, hub or switch.

Ring Topology
⚫ In this case, each computer is connected to its two adjacent computers forming a ring

Bus Topology
⚫ In this case, there is one communication line which allows communication in both directions, to which each node is connected.

Question 16

What is date

Answer 16

Data is raw facts

Question 17

What is a source document

Answer 17

This is a document that contains data that is going to be entered into a computer system. Examples of source documents are prescription invoices, medical record cards

Question 18

What is a turnaround document

Answer 18

A Turnaround Document is a document that has been output from a computer, some extra information added to it, and then returned to become a source document.
Examples include:
1.Multiple-Choice answer sheets
2.Application Forms (passport, visa, universities, etc.)

Question 19

What is human readable documents

Answer 19

These are documents that are in a form for humans to read. Many forms are filled in by hand and the employee has to read them before entering the data via a keyboard.

Question 20

What is a machine readable document

Answer 20

these are documents where the data is encoded in a way that can be easily read by computers.example barcodes, cheques with magnetic ink

Question 21

What is verification

Answer 21

This is the process during which data that has already been inputted or captured is checked to ensure that it matches the data on the source document.

Question 22

What is validation

Answer 22

Validation is a process that ensures that data entered into a database form, a web form or a computer program conforms to a set of validation rules.

Question 23

What is range check

Answer 23

This check makes sure that values fall between specified minimum and maximum values. Example (11-18)

Question 24

What is data type check

Answer 24

This check ensures that the values entered are of the correct type, for example numeric, date/time, yes/no, currency.

Question 25

What is reasonableness check

Answer 25

It determines whether values are reasonable by making sure that they don’t deviate too much from established norms. Example if someone puts the height of a 2-year-old as 5ft, it should be flagged as being unreasonable since toddlers aren’t that tall.

Question 26

What is consistency/inconsistency check

Answer 26

This check detects whether the values of two or more data items are in contradiction. Example a discount being more than the original price of an item.