PPE 2 Revision

Question 1

A computer has 1024 megabytes of RAM.

How many gigabytes of RAM does the computer have?

Answer 1

1.204 (divide number by a thousand)

Question 2

Name two items that will be stored in the RAM.

Answer 2

1. The Graphical User Interface (GUI).
2. The software applications.
3. Operating systems.

Question 3

What is the difference between ROM and RAM?

Answer 3

ROM is memory that cannot be changed by a program or user. ROM retains its memory even after the computer is turned off. RAM is a fast temporary type of memory in which programs, applications and data are stored.

Question 4

What is an embedded system?

Answer 4

A computer which forms part of an electronic device.

Question 5

How can the reliability of a system by assessed?

Answer 5

Rigorous testing.

Question 6

Explain the difference between proprietary and open standards.

Answer 6

Proprietary standards are owners and maintained by corporations, where as open standards are publicly available and modifiable.

Question 7

What is the purpose of the CPU?

Answer 7

It processes data and executes instructions.

Question 8

What is meant by clock speed?

Answer 8

The clock speed is the number of operations that the processor can carry out per second. It is measured in the unit of hertz.

Question 9

What is virtual memory and why is it used?

Answer 9

Virtual memory is temporary space taken up on the hard disk to store programs and data that are currently in use. It is used when the RAM runs out of space to deal with all the demands of the computer.

Question 10

Using an example for each, explain the difference between primary and secondary storage.

Answer 10

Primary storage is volatile. When the computer is turned off, the contents are lost. Two types are RAM and cache memory.
Secondary storage is non-volatile, so it can retain data even when the power is off. Examples are hard drives and USB sticks.

Question 11

What is the purpose of cache memory?

Answer 11

• It is fast memory located very close to the CPU.

- It allows CPU to access data fast to speed up processing.

Question 12

Name three input devices.

Answer 12

1. Keyboard.
2. Microphone.
3. Sensor.

Question 13

Name three output devices.

Answer 13

1. Printer.
2. Speakers.
3. Monitor.

Question 14

What is meant by an over flow error.

Answer 14

Overflow occurs when the largest number a register can hold is exceeded.

Question 15

What is the purpose of html?

Answer 15

HTML is standard language for describing the structure and presentation of information via the Internet.

Question 16

What is the purpose of a CD ROM?

Answer 16

It stores computer data of graphics, text and audio. They are popular for software other than multimedia applications.

Question 17

Describe what is meant by a Local Area Network (LAN).

Answer 17

Local Area Network (LAN) is a computing network that interconnects with computers within a limited area such as, residence, school, laboratory, or office building.

Question 18

Why is hexidecimal used?

Answer 18

Hexidecimal is used because it is easier to understand, it can be used to write down very large integers in a compact for. And is closely related to binary.

Question 19

Define the term database.

Answer 19

A persistent, organised store of related data on a computer system.

Question 20

Name two types of software security.

Answer 20

1. Firewall.
2. Anti Spy software.
3. Anti virus.

Question 21

What is opcode and operand?

Answer 21

Opcode is a single instruction that can be executed by the CPU. Operand is manipulated by the opcode.