stk - N5 Computer Systems

What is a pixel?

A tiny square that makes up a picture

Describe two advantages of saving a file as a vector graphic rather than a bitmap graphic.

A vector will take up less room in memory as only the objects need to be saved, not every pixel. An object in a vector is easier to edit as the whole object can be resized or deleted.

State two reasons why this image would be created using a vector graphic package rather than a bitmap graphic package.

A vector will take up less room in memory as only the objects need to be saved, not every pixel. An object in a vector is easier to edit as the whole object can be resized or deleted.

Name the part of the processor responsible for carrying out calculations.

ALU

Describe a logic operation carried out by the ALU.

AND OR NOT

State one logic operation performed by the ALU.

AND, OR, NOT, =,<,<=,>,>=,<>

Name a code that is used to represent text in a computer system.

ASCII

State which bus pinpoints the correct memory location in memory where data is to be stored.

Address bus

Describe one advantage and one disadvantage of using a solid state device rather than a hard drive.

Advantage : No moving parts so harder to break Disadvantage : Hard drives are cheaper to buy

Mary has decided to upgrade her digital camera from 4 megapixels to 12 megapixels. Describe one advantage and one disadvantage of doing this.

Advantage : The pictures will have a better resolution and therefore be better quality. Disadvantage : Each picture will take up more space on the memory card and not as many can be stored on the SD card

Alison wants to email 200 photographs but before she does so she needs to compress the photographs. Explain what effect compression may have on the photographs.

They may lose quality

State the law you are breaking if you download a film from the internet without paying for it.

Copyright Designs and Patents Act

What does the term resolution mean?

DPI

State three features of RAM.

Data can be written to RAM Data in RAM is temporarily stored Data is stored in RAM while being used by the user

Describe what should happen to old computers when a company no longer wants it.

They should be recycled

Give two functions of the ALU.

To do all the computers calculations To perform logic functions

Memory is made up of both RAM and ROM. Describe one difference between RAM and ROM.

Data is RAM is temporary, Data in ROM is permanent Data cannot be written to ROM, Data can be written to RAM

State three features of ROM.

Data is ROM is stored permanently Data cannot be written to ROM ROM contains the bootstrap loader

Explain what should happen to data when you are accessing online banking.

Data should be encrypted for saftey

State the difference between storing data in RAM and storing data on backing storage.

Data stored in RAM is stored temporarily whilst in use. Data stored on backing store is permanently stored for future use.

Alison wants to email 200 photographs but before she does so she needs to compress the photographs. Explain why Alison needs to compress the files.

To reduce their size so that they won't take as long to send

Name an input device which is built into a palmtop computer.

Touch screen

Sue's new computer has both USB 2 and USB 3 interfaces. What advantage does USB 3 have over USB 2?

USB 3 has a faster transfer rate

Describe one disadvantage of UNICODE over ASCII.

Unicode is a 16bit system which means it can store 65,536 characters, whereas ASCII is an 8bit system and can store 256 characters

Describe how ASCII is used to represent text.

Each character is given a decimal number which can be easily converted into binary. e.g. A = 65 =01000001

Give two reasons why computers use binary numbers to represent and store data.

Easier to perform calculations Less Degradation of signal

State a development in security software that makes customers feel more secure about buying online.

Encryption

A newspaper is going to publish stories by its readers on its website. What must the newspaper company do to ensure that is does not break copyright, designs and patents act?

Get a disclaimer from the reader stating that they wrote it.

Alison finds a graphic on the internet and incorporates it into a new logo she is designing for her company. Explain how Alison could use the graphic legally.

Get permission from the creator

Peter has moved into a new flat and he has discovered that he can access his neighbours wifi. Peter decides to get his own wired network installed. Give two reasons for this decision.

He should get more bandwidth. He is not breaking the law

Explain the difference between high level language code and compiled code.

High level languages use English like statements Compiled code is machine code (binary)

State one disadvantage for a computer using binary.

Humans do not understand binary

Most modern computers use Unicode rather than ASCII to represent text. State one advantage of Unicode when compared to ASCII.

Unicode is a 16bit system which means it can store 65,536 characters, whereas ASCII is an 8bit system and can store 256 characters

How is memory organised so that data can be stored and retrieved by the processor?

Unique Storage Locations

A program calculates the wage of a worker as £314.36 Describe how a number like 314.36 is stored in the computer.

Number is broken down into mantissa and exponent. Each of these are stored separately in memory.

Explain how real numbers are stored using floating point representation.

Number is broken down into mantissa and exponent. Each of these are stored separately in memory.

Inside a computer the RAM and processor are separate. Describe how data is transferred between these two components.

On the data bus

Explain how photographs are stored in computer memory.

Photos are stored as a bitmap. Each picture is broken down into tiny pixels and each pixel is stored as a binary pattern.

Describe how a bitmap is stored in a computer.

Picture is broken down into tiny pixels and each pixel is stored by a binary pattern.

Marion is looking at two laptops in a shop and considering which one to buy. State two criteria that you would consider when purchasing a new laptop.

Processor speed Memory HDD capacity

Explain why programs written in a high level language need to be translated.

Processors only understand binary and translators convert the high level language into binary.

Mike has recently installed a wireless network in his house. What should he do in order to stop his neighbours accessing the network?

Put a secure password/passkey on the network

Rohit fixes all the errors in his code, but before he can save the code, the computer reboots unexpectedly. When the computer rebooted, Rohit's program was lost. What part of the computer was storing Rohit's program?

RAM

When typing a program into the computer, where is the program stored before it is saved to backing store?

RAM

What is the function of the data bus?

The data bus allows data to be transferred between the processor and memory

Why is the address bus uni-directional whereas the data bus and control bus are bi-directional?

The data bus needs to send data to and from memory. The control bus needs to send signals all over the computer. The address bus only needs to send that address to memory of the location which needs to be accessed

Explain one advantage to using cloud storage compared to local server storage.

The host company will do backups for you. You can access your work for anywhere you can get online

Describe how bit-mapped images are stored.

The image is made up of pixels and each pixel is represented in memory as a binary pattern

Explain how the number 37.4 is stored in a computer system.

The number is broken down into the mantissa and exponent and both are stored separately in memory.

What is a register?

The processor's own temporary storage location

Describe what you could change on your digital camera to increase the number of pictures you can store on an SD card, without adding a higher capacity SD card.

The resolution

Describe two advantages of replacing desktop computer with palmtop computers.

They are portable and can be carried around and used in more than 1 location.

Describe the purpose of the address bus.

- The address bus holds the address of the memory location being accessed

How many bytes are there in a kilobyte?

1024

Data is stored in memory using bits. What is the largest positive number that can be stored using 7 bits?

127

What is the largest positive number that can be stored using 4 bits?

15

Processor 1 - 2.4 GHz Processor 2 - 2.6 GHz Processor 3 - 3.8 GHz State the fastest clock speed shown above.

3.8

How many bits are used to store a text character using ASCII?

7 bits

What is a byte?

8 bits

If a graphic is described as high resolution, what does that tell you about the amount of storage it will need? Give a reason for your answer

A high resolutions means more pixels and as each of these pixels need to be represented in memory the amount of storage will be high.

What is a bit?

A single Binary Digit

Explain how data is transferred from Memory to the processor.

Along the Data Bus

Text is stored as ASCII. What does ASCII stand for?

American Standard Code for Information Interchange.

While a program is being developed an interpreter is used rather than a compiler. Explain why an interpreter is used at this time.

An interpreter will convert into binary and report errors at the end of each line. This meant that the programmer will be given syntax errors as soon as they are made.

Describe two functions of a tablet that are not always available on a laptop.

Biometric login touchscreen motion sensor

Describe two ways in which this image could be represented in memory.

Bitmap image - The image is made up of pixels and each pixel is represented in memory as a binary pattern Vector Image - The graphics are stored by their mathematical attributes. E.g. their co-ordinates, line width etc

When Carolyn switches on her computer, system software in ROM finds and loads the OS. Name this system software in ROM.

Bootstrap Loader

Mike has discovered that his next door neighbour has been accessing his wireless network. State which law Mike's neighbour has broken.

Communications

There are many ways of comparing computer performance. Name one of the simplest and most widely used.

Compare processor speed

Describe two functions of an interface.

Compensate for differences in speed Compensate for differences in voltage Compensate for differences in code

Modern computers come with a number of different interfaces such as USB or SATA. Describe two functions of an interface.

Compensate for differences in speed Compensate for differences in voltage Compensate for differences in code

State which law you are breaking by deliberately sending a virus.

Computer misuse act

The arithmetic and logic unit is part of the processor. Name the other two parts of the processor.

Control Unit Registers

Give two functions of the control unit.

Control the fetching and executing of instructions

Describe the benefit of adding more memory to your computer.

More data can be stored in memory when the processor is using it and this will make the computer run faster.

What connects a computer system to a peripheral to allow them to communicate.

Interface

Pete wants to buy an external hard drive to back up the data on his computer. State two characteristics he should consider when making the purchase.

Interface; Capacity; Solid state or magnetic.

Many publications on the internet are saved in pdf format. What advantages does saving your file as a pdf have over other formats?

It's a standard file format and therefore compatible with most systems.

Name a standard file format for saving a graphic file.

Jpeg bmp gif

Describe two different ways that computers can use biometric technology.

Log in to the computer Log in to apps/files

Solid state storage devices are much more difficult to damage than magnetic devices. State two reasons why some managers are still using magnetic disks.

Magnetic disks are still cheaper than SSDs Magnetic disks are still more widely available than SSDs

What effect would upgrading a processor have on a computer?

Make the computer faster

What do the letters RAM stand for?

Random Access Memory

What do the letters ROM stand for?

Read Only Memory

Describe one way of storing a real number in computer memory.

Real number is stored as floating point. The number is broken down into mantissa and exponent and both are stored separately in memory.

Explain what a company should do before storing any personal data.

Register with the data protection registrar

A computer processor is made up of three parts. Name the part responsible for the temporary storage of data within the processor.

Registers

Dot has received a text file from a friend but is unable to access it using her text processing software. Explain how you can ensure that another computer user can access the text file on their computer.

Save it using a standard file format. Save it as an ASCII file

Alison finds a graphic on the internet and incorporates it into a new logo she is designing for her company. Explain why this is illegal.

She does not have the creators permission.

Michelle's friend says that she should connect her 30 computers using a peer to peer network rather than a client server network. Give two reasons why this is not a good idea.

She would need to back up the 30 computers on the peer to peer, on a client server you only need to back up the server. She would need to put anti-virus/filtering software on the 30 computers, on a client server you only need to put the software on the server.

Suggest one use for ROM on a computer system

Store the bootstrap loader

Explain, with reason, what type of computer is best suited to travelling salesmen who are going to show customers their products.

Tablet computer - a portable device that can store pictures and details of the products and can connect to the internet if needed. Laptop computer - a portable device that can store pictures and details of the products and can connect to the internet if needed.

What is the function of the address bus?

The address bus holds the address of the memory location being accessed.

State how a computer system represents characters.

Using ASCII system. Each character is given a decimal number and that number is converted into binary. E.g. A = 65 = 01000001

Describe how vector images are stored.

Vector graphics are stored by their mathematical attributes. E.g. their co-ordinates, line width etc

Describe what data security precautions companies must take before computers are decommissioned.

Wiping the hard drive

Explain the advantage of saving your work onto the cloud.

You can access your work anywhere you can get on the internet. The host company is responsible for backing up your data

Write the following in order of size, starting with the smallest: byte - gigabyte - kilobyte - megabyte

byte, kilobyte, megabyte, gigabyte

State which type of computer system would be used by a bank to process large amounts of data at high speed.

mainframe

State two advantages for a computer using binary.

• Easier to do calculations • Less degradation of signal