1.2.3 - Units

Question 1

Why do computers use binary to represent data?

Answer 1

A computer is built of switches, either: on and off, which correspond to 1 and 0. (base 2)

Question 2

What are the standard units of data storage, from smallest to largest?

Answer 2

Bit,
Nibble (4 bits),
Byte (8 bits),
Kilobyte (KB),
Megabyte (MB),
Gigabyte (GB),
Terabyte (TB),
Petabyte (PB).​

Question 3

How do you convert between different units of data storage?

Answer 3

4 bits = 1 nibble,
8 bits = 1 byte,
1,000 bytes = 1 kilobyte (KB),
1,000 kilobytes = 1 megabyte (MB),
1,000 megabytes = 1 gigabyte (GB),
1,000 gigabytes = 1 terabyte (TB),
1,000 terabytes = 1 petabyte (PB).

Question 4

How do you calculate the file size of a sound recording?

Answer 4

Sound file size = Sample Rate × Duration (s) × Bit Depth

Question 5

How do you calculate the file size of an image?

Answer 5

Image file size = Colour Depth × Image Width (px) × Image Height (px)

Question 6

How do you calculate the file size of a text document?

Answer 6

Text file size = Number of Characters × Bits per Character