Synoptic / cap wrong doings

Question 1

Encryption

Answer 1

Encoding data so that is can only be viewed by the intended viewer

Question 2

Why normalise floating point numbers

Answer 2

To maximise accuracy

Question 3

Nyquist’s theorem

Answer 3

Sample at a frequency of twice the rate of the highest frequency

Question 4

What is exception handling used for

Answer 4

Handling runtime errors To stop a program from crashing

Question 5

Subroutine

Answer 5

A self contained set of commands that can be called from different parts of a program

Question 6

Difference between local and global variables

Answer 6

Global variables can be used within the whole program whilst local variables can only be used within the subroutine.

Question 7

Why is it good practise to use local variables

Answer 7

-Take up less memory
-Memory allocated to local variables can be reused
-Using local variables makes subroutine self contained

Question 8

Pixel

Answer 8

Smallest unit which can be drawn on a screen

Question 9

Sampling rate

Answer 9

Number of samples taken per second

Question 10

Process of ADC (Analogue to digital converter)

Answer 10

ADC takes samples of the analogue signals at regular intervals. Samples are quantised. Each sample is assigned a binary value.

Question 11

One difference between Unicode and ASCII

Answer 11

Unicode can store more characters

Question 12

Array

Answer 12

Fixed sized sequential collection of elements of the same data type

Question 13

Records

Answer 13

Composed of related data

Question 14

Pointer

Answer 14

Declare a variable to point a physical address in the memory

Question 15

Selection

Answer 15

Do a set of statements based on conditions
“Branching”

Question 16

String concatenation

Answer 16

Join together seperate strings into a single string

Question 17

Algorithm

Answer 17

a sequence of steps (to complete a task)

Question 18

Sample resolution

Answer 18

The sample resolution is the number of bits used to represent/store each sample;

Question 19

Describe what libraries are and why programmers use them.

Answer 19

Provides routines that can be included/used in a program;

Improves the speed of development // reduces workload

Question 20

A vector can be represented:

Answer 20

As a list
As a 1-D array
As a dictionary (which can be considered to be representing it as a function)
Graphically (as an arrow, demonstrated above)
Using set notation

Question 21

Recursive Subroutine

Answer 21

Subroutine that calls itself

Question 22

Time complexity for merge sort

Answer 22

n log(n)