MATSEC Past PapersMay 2010

• Paper 1• Paper 2A

What is the difference between each of the following pairs of items?

Syntax ErrorCaused by forgetting

certain codes and statement structures

Not obeying the programming language’s rules

The compiler will find these errors

Ex. System.out.plintln(“hi”);

Logical ErrorA mistake found in

the actual design of a program

Use of the wrong mathematical operation

Found by gaining the wrong results

Ex. Average = 10+11+2/3

10

What is the difference between each of the following pairs of items?

ByteA byte is a group

of 8 bits

WordA word is a group

of bits that are handled as a unit by the instruction set of the CPU

AssemblerAssembler

translates Assembly language into machine code.

CompilerCompiler

translates a high level language source code into executable code

What is the difference between each of the following pairs of items?

Integer data typeCan only store

whole numbers

Real data typeCan store

numbers with decimal places

CAMcomputer aided

manufacturingProcesses models

from CAD and manufactures them using machines

CADcomputer aided

design3D sketches of

an object

Give one reason why:Passwords are required To prevent unauthorised access to files

and other resources

4

The Data Protection Act as established To protect sensitive data of the

individual and prevent unauthorised distribution and access of data.

Backups are madeSo that if the original files are corrupted

they can be replaced with their backups.Software is copyrighted

it’s the right of the author which states that software cannot be copied or modified

Fill in the missing terms;The ALU performs arithmetic and logical

operations

5

A character code that is widely used in computers is ASCII or UNICODE

Two types of optical storage media are CD and DVD

A computers main memory stores both data and addresses

A parity bit is an extra bit that is added to a byte to help detect errors

Which communication medium transfers data as pulses of light?

Fibre optic cables

1

Telephone lineCable line Satellite

List another 3 types of communication media

3

Identify Two advantages and two disadvantages of using a wireless network at home

4

Advantages: Computers can be placed anywhere

There is no need for cables.

Disadvantages: More security risk,

Sometimes signal doesn’t reach all places.

A computer currently has 512MB of main memory and the owner wishes to upgrade it to 1 GB. If the memory chips available have a capacity of 256 MB, how many of these chips are needed?

2

512 / 256 = 2

Mention two advantages of having a larger memory The computer will be much fasterMultitasking will not slow down the computer

2

Describe a problem for which a computer simulation would be a suitable method of solution and explain why a computer simulation would be the most suitable method in this case

3

Training an airplane pilot, since an airplane is dangerous to fly without any experience since it can cause a lot of damage, the pilot has to be trained in a safe environment first. (Other simulations: space exploration, soldier training)

Briefly describe two methods of validating data and for each method give an example of invalid data

4

Method 1: Range check, if a month is inputted, it has to be checked if it’s between 1 and 12.

Method 2: Check digit, if a number is inputted (such as credit card number) a special algorithm is carried out and it checks if the inputted number is valid or not.

Mention 3 types of documentation that are produced during software development and state why each is needed

6

User: helps the user on how to use the basic functionality of a program.

Technical: helps the technician solve problems using troubleshooting and how to conduct any changes to the program.

Programmer: Helps programmer understand the program through graphical representations such as flowcharts and comments.

Write the binary equivalent of the hexadecimal number 4A2

4 A = 10

8 4 2 1 8 4 2 1

0 1 0 0 1 0 1 0

If the ASCII code equivalent to the letter A is 65. Which letter does the binary number 01001010 represent

2

65 66 67 68 69 70 71 72 73 74

A B C D E F G H I J

74

J

01001010 = 74

What is the largest number that can be stored in an 8-bit register

2

128

64 32 16 8 4 2 1

1 1 1 1 1 1 1 1

128 + 64 + 32 + 16 + 8 + 4 + 2 + 1 = 255

Consider the terms below :flash memory, scanner, mouse, modem, RAM

4

Which of the above allows digital data to be transmitted over telephone lines?modemWhich of the above is a form of non-volatile storage?Flash memory

Which of the above can translate drawings and photos into digital format?Scanner

Which of the above is a form of volatile storage?RAM

Consider the truth table below

A B C X Y Z

0 0 0 0 0 1

0 0 1 0 1 0

0 1 0 0 0 1

0 1 1 0 1 0

1 0 0 0 0 1

1 0 1 0 1 0

1 1 0 1 0 1

1 1 1 1 1 0

Draw the logic circuit corresponding to the truth table 9

A

BX

C

Y Z

Paper 2 AWe will be doing a class correction of paper 2A together tomorrow so please bring this paper worked out