1.2: MEMORY AND STORAGE 2.0

Question 1

What is a major disadvantage of SSDs? Give an example.

Answer 1

• expensive, tends to be smaller in capacity than other types.
• For example, a solid-state drive that holds 256 GB might be of a similar cost to a hard disk with several terabytes capacity.

Question 2

How does power requirement correlate to the efficiency of SSDs?

Answer 2

-require little power, making them ideal for portable devices where battery life is a big consideration.

Question 3

Considerations for an appropriate type of secondary storage (6) and their relevance.

Answer 3

Cost - cost per gigabyte (GB)?
Capacity - how much data can the medium hold?
Speed (of access) - how quickly can data be transferred to and from the medium?
Portability - how portable is the medium? Does it need to be portable?
Durability - how robust is the medium, and how robust will it need to be?
Reliability - how resilient and long-lasting is the medium?

Question 4

SPEED:

Answer 4

SSD: fast as there are no moving parts

MAGNETIC: slow due to moving parts

OPTICAL: slow and limited as there are moving parts

Question 5

CAPACITY:

Answer 5

MAGNETIC: large

SSD: sufficient

OPTICAL: low

Question 6

COST:

Answer 6

MAGNETIC: cheapest per GB

OPTICAL: cheap for small storage

SSD: expensive

Question 7

PORTABILITY:

Answer 7

SSD: highly portable and lightweight

OPTICAL: highly portable and light weight

MAGNETIC: internal drives are not portable, external drives are large in size.

Question 8

RELIABILITY:

Answer 8

SSD: extremely reliable
MAGNETIC: very reliable
OPTICAL: good in the medium term

Question 9

DURABILITY:

Answer 9

SSD: extremely durable

MAGNETIC: good when not in use, can be affected by magnetic fields and heat

OPTICAL: susceptible to scratches and will degrade over time with exposure to sunlight

Question 10

what form is data stored in inside of a computer?

Answer 10

-binary form

Question 11

what is a bit?

Answer 11

the smallest unit of data a computer can use.

Question 12

what must happen to denary numbers before they can be processed/ used by a computer?

Answer 12

-must be converted into their binary equivalent before a computer can use them.

Question 13

what is Overflow?

Answer 13

the result of a binary calculation exceeds 8 bits/ the denary value 255

Question 14

what do you write in a binary overflow error?

Answer 14

00000000

Question 15

why are overflow errors bad?

Answer 15

-overflow can have serious consequences for the validity of calculations.

Question 16

through what process are binary numbers multiplied/ divided?

Answer 16

-through a process called shifting.

Question 17

how do you multiply and divide with binary shifts?

Answer 17

• multiply: shift to the left

- divide: shift to the right

Question 18

why is hex useful?

Answer 18

-large numbers can be represented using fewer digits.

Question 19

equation for

sound file size:

Answer 19

sound file size = sample rate x duration (s) x bit depth

Question 20

equation for:

image file size

Answer 20

image file size = colour depth x resolution (image height (px) x image width (px))

Question 21

equation for:

text file size

Answer 21

text file size = bits per character x number of characters

Question 22

explain why computers represent data in binary form:

Answer 22

• Computers consist of transistors / logic circuits/gates. ​

- Which only have two values: on (1) or off (0)

Question 23

explain why hexadecimal is used by computer scientists: (2)

Answer 23

• Easier/ faster to convert to and from binary.​
• composed of fewer digits: 8 bits are represented by 2 characters which thereby makes it easier for humans to remember and makes it less susceptible to human errors

Question 24

what is Binary? (2)

what is denary/ decimal?

Answer 24

• Data format that can be represented by electrical voltages,
• which can then be processed by logic gates in the computer

-numbers we use in real life

Question 25

can denary be processed by the computer?

Answer 25

no

Question 26

what does the term ‘encoding’ mean?

Answer 26

Converting data into a binary format so that that it can be stored and processed by a computer

Question 27

what are logic gates?
what do logic gates only process?
what do we use along with it? and for what reason?

Answer 27

• The basic building block of digital computers
• 1s and 0s
• use binary to encode all data

Question 28

what does the term ‘base’ refer to?

what is the base of binary, denary/decimal and hex?

Answer 28

-number of digits used by a number system

binary = 2
denary = 10
hex = 16

Question 29

what do the terms ‘most significant bit’ and ‘least significant bit’ refer to?

Answer 29

MSB-leftmost bit of a binary number- column with the largest place value

LSB-furthest right bit in a binary number

Question 30

what is a possible issue that could be encountered with a right shift?

Answer 30

-an issue with precision occurs where odd numbers are divided since a standard byte cannot represent fractional numbers.