CS1

Question 1

Denary to binary

Answer 1

Successive or subtraction

Question 2

Binary to decimal

Answer 2

Replaces ones with places and add

Question 3

Binary addition

Answer 3

In binary addition change the 0 to a 1 if there is already a 1 then move that 1 to the left position

Question 4

Hexadecimal

Answer 4

0
1
2
3
4
5
6
7
8
9
a
b
c
d
e
f

Question 5

Hexadecimal to decimal

Answer 5

Use values to convert and then add all

Question 6

Decimal to hexadecimal

Answer 6

Divide number by 16 then take the result of the final subtraction as the remeinder, repeat as much times as possible

Question 7

Hexadecimal advantages

Answer 7

Shortcut to represent binary numbers

Two hex digits make 1 byte (8 bits)

Hexadecimal are used in colors, error messages, assembly languages programs, MAC addresses

Question 8

Hexadecimal to binary

Answer 8

Separate the hexadecimal number by digits and then get the nibble then just write them together

Question 9

Binary to hexadecimal

Answer 9

Separate the binary into nibbles and then convert those nibbles and write together

Question 10

Storage units

Answer 10

8 bits = 1 byte 
(x1000)
1000 bytes = 1 Kilobyte
1,000,000 bytes = 1 Megabyte
1,000,000,000 bytes = 1 Gigabyte
1,000,000,000,000 bytes = Terabytes

Question 11

Overflow

Answer 11

An overflow error occurs when a value outside this limit should be returned, this means that the largest number that a register can hold is exceeded.

An overflow error will occur if the value is greater than 255 in an 8-bit register

Question 12

Shifts

Answer 12

Multiplications or divisions

2^0 = 1 shift = x or / 1
2^1 = 2 shifts = x or / 2
2^2 = 3 shifts = x or / 4

Question 13

Multiplication

Answer 13

Are left shifts, after shifting a zero is added to the right, if a 1 exceeds the limit then it will cause and overflow and we can loose data.

Question 14

Division

Answer 14

Are right shifts, after shifting a zero is added to the left, a 1 bit can be lost, it doesn’t cause and overflow, but it loses accuracy.

Question 15

What do you use to get negative binary numbers

Answer 15

Two’s complement

Question 16

Binary is positive

Answer 16

MSB (Most Significant Bit) is 0

Question 17

Binary is negative

Answer 17

MSB (Most Significant Bit) is 1

Question 18

Two’s Complement

Answer 18

First convert the decimal number to binary
Obtain the 1’s complement (invert 0’s and 1’s)
Add 1

Question 19

Binary subtraction

Answer 19

Decimal to binary
positive number
+ negative number

Question 20

Negative other way

Answer 20

Use MSB as indicator and then add those positive to the negative one.

Question 21

How many bits ASCII code use?

Answer 21

7 bits

Question 22

What is ASCII used for?

Answer 22

To represent numbers, letter, punctuation and non printing commands.

Question 23

How many bits does extended ASCII use?

Answer 23

8 bits

Question 24

What does extended ASCII cover?

Answer 24

Non-English characters, graphics symbols and mathematical symbols.

Question 25

What does Unicode cover?

Answer 25

Works with different languages, non-English characters, graphics symbols, mathematical symbols and even emojis are also in unicode.

Question 26

How many bits does Unicode use?

Answer 26

UTF-8 uses 8, variable width (it allows expanding to more bits)
UTF-16 uses 16 bits, variable width (it allows expanding to more bits)
UTF-32 fixed-width encoding. Each character takes exactly 32-bits

Question 27

Bit depth in sound is?

Answer 27

The amount of bits that are used to cover sample values. (The more there are the better sound quality but also greater size)

Question 28

Sampling rate in sound is?

Answer 28

The rate at which the bit depth is sampled at. (measured in Hz or Hertz)

Question 29

How is sound recorded

Answer 29

Analog signal gets converted to digital and then it is interpreted and outputted.

Question 30

Sound File Size Formula

Answer 30

Size of audio file (bits) ＝ Number of sample per second (Hz) ✖ Number of bits per sample (8 bit) ✖ Length of sample in seconds (Sec, if not in seconds, then convert)

Question 31

What is color depth in images

Answer 31

How many colors can be represented on an image. With a color depth of n bits, a computer can represent 2n different colors.

Question 32

RGB colors in images

Answer 32

Computer use RGB to represent colors by mixing values of red, green and blue. It uses hexadecimal values

Question 33

Image resolution

Answer 33

Width of pixels x height of pixels

Question 34

Image File Size Formula

Answer 34

File size (bits) = pixels width x pixels height x color depth (16 bit or whatever)

Question 35

Compression

Answer 35

A method of reducing file sizes, particularly in digital media such as photos, audio and video.

Question 36

Lossy

Answer 36

Means that data is lost forever.

It is good to use when specific file things aren’t needed. (Specific colors, shades, tones)

JPEG, Audio files and videos.

Question 37

Lossless

Answer 37

Means that no data is lost.

It is good when you want to compress a file but don’t want to loose anything. ( It does not achieve the same file size reduction as lossy compression.)

PDF, GIF, TIFF and PNG

Question 38

Compression advantages

Answer 38

Less internet bandwidth is needed to down/upload files.
Less storage space needed
Quicker to transfer
Smaller files reduce congestion on the internet.
Audio and video files can be streamed.