Chapter 1 Data Representation

Question 1

What does hexadecimal do

Answer 1

Represents large amounts of binary data in a more manageable and readable format.

Question 2

Why is using Hexadecimal beneficial (3 points)

Answer 2

1) Takes fewer digits to represent binary.
2) easier to read.
3)numbers with more bits are more prone to errors.

Question 3

What are Logic Gates

Answer 3

electronic devices that perform logical operations on binary data

Question 4

What is the use of logic gates

Answer 4

used to process binary data by applying Boolean Logic

Question 5

What are binary shifts

Answer 5

used to multiply or divide binary

Question 6

Why is binary useful

Answer 6

converts any form of data into binary in order for it to be processed by a computer

Question 7

What is text

Answer 7

collection of characters

Question 8

What is a character set

Answer 8

collection of characters that correspond to binary codes that represents them

Question 9

How does ASCII work

Answer 9

assigns a unique 7-bit binary code to each character.

Question 10

How does UNICODE work

Answer 10

uses variable length encoding assigning unique codes to each character.

Question 11

what is a disadvantage of ASCII

Answer 11

does not support other languages other than english

Question 12

What is a disadvantage of UNICODE

Answer 12

Requires more bits per character -> causing larger file sizes and slower processing times

Question 13

What is sampling

Answer 13

How sound is converted into digital form

Question 14

What are 2 ways to increase the quality of a sound

Answer 14

1) increasing the sample rate
2) increasing the sample resolution

Question 15

What is Sample rate

Answer 15

Number of samples per second

Question 16

What happens when increasing sample rate

Answer 16

the quality of the sound increases, but the file size increases

Question 17

What is sample resolution

Answer 17

number of bits per sample

Question 18

What happens when increasing the sample resolution

Answer 18

The quality of the sound increases, this allows for a more accurate data representation of sound, but increases the file size.

Question 19

What are 2 types of sound files

Answer 19

1) MIDI
2) MP3

Question 20

What are the features of MIDI file

Answer 20

1) stores a set of instructions
2) does not store actual sounds
2)data in the file has been recorded using digital instruments.

Question 21

What are the features of MP3

Answer 21

1) format for digital audio
2) actual recording of the sound
3) recorded using a microphone

Question 22

formula to find resolution

Answer 22

width x height

Question 23

how to find colour depth

Answer 23

2^of how many colours there are

Question 24

how to find total number of bits

Answer 24

number of pixels x colour depth

Question 25

how to find number of bits per second

Answer 25

sample rate x sample resolution = num of bits per second

Question 26

What is colour depth?

Answer 26

Number of bits representing a colour

Question 27

What is resolution

Answer 27

Number of pixels in an image

Question 28

What happens when increasing colour depth

Answer 28

more realistic image but needs more storage space

Question 29

What happens when increasing the resolution

Answer 29

increasing resolution allows for a clearer image but a needs more storage

Question 30

Why does the file size increase when the image resolution and colour depth increase?

Answer 30

More pixels and colours require more binary data to represent them.

Question 31

What is an overflow error

Answer 31

when the binary addition exceeds the maximum value that can be represented.

Question 32

What happens if a binary number shifts to the left

Answer 32

multiplication to a power of 2

Question 33

What happens if binary shifts to the rights

Answer 33

division to a power of 2

Question 34

what is the use of hexadecimal

Answer 34

- error codes - mac address - nic (network interface card) - colour codes - blockchain hash - ipv6