Represent text sound and graphics

Question 1

What does ASCII stand for?

Answer 1

American Standard Code for Information Interchange

Question 2

How many bits does ASCII use?

Answer 2

7

Question 3

How is it structured?

Answer 3

A-65 s mall a-97

Question 4

What is a character set?

Answer 4

A list of characters recognised by software and hardware

Question 5

What is the 8th bit for

Answer 5

Error checking(even number of 0’s and 1’s)

Question 6

Give 1 benefit of the extended ASCII code

Answer 6

additional £ sign

Question 7

What was the task of UNICODE?

Answer 7

To create a character set used globally

Question 8

What is ord used for?

Answer 8

To find out a character’s ASCII code

e.g. ord(“A”)is 65

Question 9

What is difference between amplitude and frequency?

Answer 9

Amplitude is how loud the noise is but frequency is how long it is

Question 10

What does the microphone do?

Answer 10

Converts sound to electrical energy

Question 11

What is the sound-card responsible for?

Answer 11

Converting electrical signal from microphone to binary signal

Question 12

What is sample rate?

Answer 12

Samples sound wave at regular intervals

Question 13

What are the steps?

Answer 13

1.Sound waves are analogue so changes continuously
2.To record sound it is first recorded with a microphone
which converts sound energy to electrical energy
3. Analogue electrical signal sampled at regular intervals-sample rate by the sound card
4. At each sampling the value of electrical signal is rounded up or down.And binary value point is recorded.

Question 14

How do you work out file size

Answer 14

File size (bits)=Sample rate(Hz)*Sample resolution
 *Length(sec)

Question 15

What are pixels?

Answer 15

Small dots that make up a bitmap image

Question 16

How do you work out file size in images?

Answer 16

File size(bits)=image resolutioncolour depth=width* height*colour depth