1. Data Representation Flashcards
1
Q
Why a computer can only process data in binary
A
- data is processed in a computer using logic gates
- that only have two states, 0 or 1
2
Q
Uses of hexadecimal
A
- colour codes in HTML/CSS
- error messages
- locations in memory
- memory dump//debugging
- IPv6 address
- ASCII/Unicode
- assembly language
- MAC addresses
- URLs
3
Q
Advantages of hexadecimal
A
- easier to understand/read/write by humans
- faster to debug
- less likely to make a mistake
- shorter representation/takes up less screen space
4
Q
Overflow error
A
- the result of the calculation is greater than 255
- there are more bits in the answer than the register can hold
5
Q
Character set
A
- all the characters and symbols that can be represented by a computer system
- each character and symbol is assigned a unique value
6
Q
Sample rate
A
the number of samples taken per second
7
Q
Sample resolution
A
the number of bits per sample
8
Q
Sample resolution and recording accuracy
A
- higher sampling resolution creates a more accurate recording
- more bits allocated to each amplitude
- amplitudes can be more precise
- a wider range of amplitudes can be recorded
9
Q
How an analogue sound wave is converted into digital form
A
- (analogue) sound wave is sampled
- …amplitude/height (of wave) is measured
- …at set/regular time intervals
- each sample/measurement is stored as a binary number
- the binary number for each sample is stored sequentially
10
Q
Image resolution
A
total number of pixels in an image, calculated by height times width
11
Q
Lossless compression
A
- a compression algorithm is used
- …such as RLE
- repeating words/characters/phrases are identified/patterns are identified
- …and indexed
- …with number of occurrences
- …with their position
12
Q
Reasons for file compression
A
- faster to transmit
- takes up less bandwidth
- to save storage space
- to make it small enough to attach to an email
