1.2:MEMORY AND STORAGE PWH

Question 1

What is a synonym for memory?

Answer 1

Storage

Question 2

What are the three categories of memory?

Answer 2

Primary
Secondary
Tertiary

Question 3

What is contained in the primary storage?

Answer 3

Cache
Registers
ROM
RAM

Question 4

Where is the primary storage located?

Answer 4

Close to the CPU

Question 5

What are the characteristics of RAM?

Answer 5

Fast access
Volatile
Contains current programs and instructions
Link between the CPU and hard drive

Question 6

What are some characteristics of ROM?

Answer 6

Non volatile
Contains essential commands
Contains POST and BIOS

Question 7

What is virtual memory?

Answer 7

The use of secondary storage as memory when the RAM is full

Question 8

What is a disadvantage of virtual memory?

Answer 8

It is much slower than other types of memory
The capacity is set by the operating system is around 1-2GB

Question 9

What are the three types of secondary storage?

Answer 9

Magnetic
Solid state
Optical

Question 10

Which examples of secondary storage can be used in magnetic storage

Answer 10

HDD
Tape

Question 11

Which examples of secondary storage can be used in solid state storage

Answer 11

SSD
Flash Drive
SD card
USB

Question 12

Which examples of secondary storage can be used in optical storage

Answer 12

CD
DVD
Blu-ray

Question 13

What are the 6 dimensions to compare storage?

Answer 13

Cost (£/Gb)
Capacity
Portability
Speed (Gb or Mb/s)
Durability (Read/write)
Resiliency (Sturdy)

Question 14

What are tracks?

Answer 14

The name of the concentric circles on the HDD

Question 15

How does magnetic storage read and write data?

Answer 15

Disk heads mounted on mechanical arms

Question 16

How are the 1s and os stored in magnetic storage?

Answer 16

polarities

Question 17

What are the pros of magnetic storage?

Answer 17

Cheap
Large storage capacity
Fast access speeds

Question 18

What are the cons of magnetic storage?

Answer 18

Not robust
Life span of 4-5 years
Slower than others

Question 18

What are the cons of magnetic storage?

Answer 18

Not robust
Life span of 4-5 years
Slower than others

Question 19

How is the data stored in optical storage?

Answer 19

In binary in a spiral from the middle out
Grooves (0)

Question 20

What are the 4 layers of a CD?

Answer 20

Label
Acrylic
Aluminium
Plastic

Question 21

Which layer does the laser reflect off?

Answer 21

The aluminium layer

Question 22

Where does the laser hit if it if is a 1

Answer 22

The sensor

Question 23

What are the pros of optical storage?

Answer 23

Cheap
Portable
Easy to produce

Question 24

What are the cons of optical storage?

Answer 24

Less storage Slow write Easily damaged

Question 25

Non volatile can also be called?

Answer 25

Persistent

Question 26

How does solid state storage read and write data?

Answer 26

Trapping electrons

Question 27

What are the pros of solid state storage?

Answer 27

Fast access Robust-no moving storage Portable-physically small

Question 28

What are the cons of solid state storage?

Answer 28

Expensive Limited read/write

Question 29

what is metadata?

Answer 29

data about data the data stored in a file alongside the actual files data identifies stuff like: the type of image, when it was created, who it was created by, the image dimensions, the colour depth

Question 30

what is lossy compression?

Answer 30

permanently removes some data used for sound (some sounds can’t be heard used for images (removes tiny details like colour differences)

Question 31

what is lossless compression?

Answer 31

eliminates redundant information without losing quality the algorithm finds groups of repeating data and records the data once along with the number of repetitions RUNLENGTH ENCODING

Question 32

what are the benefits of compression?

Answer 32

smaller files = fewer packets = faster transmission time the stream will decompress when playing reduces download times-^ makes streaming possible images in websites appear faster reduces space on disk/server

Question 33

What does a binary shift to the right do?

Answer 33

Divide a number by 2

Question 34

How many bits does ASCII use

Answer 34

7

Question 35

How many bits does extended ascii use

Answer 35

8

Question 36

How many bits does unicode use per character?

Answer 36

161

Question 37

what is bit depth

Answer 37

the number of bits per pixel

Question 38

how is resolution measured

Answer 38

dots per inch DPI

Question 39

how is resolution calculated?

Answer 39

the number of pixels in an area (wxh)

Question 40

what is colour depth

Answer 40

the number of bits available to show the colour of each pixel

Question 41

how many colours can you fit in 5 bits

Answer 41

32 (2^5)h

Question 42

how do you calculate the bits used

Answer 42

no. of pixels x colour depth

Question 43

how do you calculate file size

Answer 43

sample rate x bit depth x duration