Section 4 - Data Representation Flashcards Preview

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Flashcards in Section 4 - Data Representation Deck (9)
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1

Describe how binary is used to represent data in computers

Computers are made up of logic circuits which use high and low voltages to represent 1s and 0s.

2

Define the term 'character set'

A character set is a collection of characters a computer recognises from their binary representation.

3

Convert the hexadecimal 4E into decimal

78
(4×16 = 64, 64+14 =78)

4

Define the term 'image resolution'

The size of an image (width × height) in pixels.

5

Describe how the number of bits used per pixel affects the colours in an image.

The number of bits per pixel determines the number of possible colours and so increases the amount of unique colours an image has available to use.

6

Explain why compression is used for audio files

Audio files can be very large especially for long podcasts. Compression is used to reduce the overall size of the audio file with some acceptable loss of quality.

7

What type of compression is Huffman coding?

Lossless

8

Explain how increasing the sampling rate can affect the quality of the sound file.

Increasing the sampling rate means that more samples are taken every second. The sound quality will be better as the file will more closely match the original.

9

What is the hexadecimal representation of the letter P?

50
(Binary = 01010000, split into nibbles = 5 and 0 which = 50)