Flashcards
Data rep flashcards
Cards in this deck (29)
- 1Why do computers use binary?Computers only understand binary as it uses a series of on and off switches represented as either a 1 or a 0.
- 2What does 1 bit mean?A single 1 or 0
- 3How many bits in a Byte?8 bits
- 4What is a nibble?4 bits or half a byte.
- 5How many bytes in a Kilobyte?1000 bytes
- 6How many bytes in a megabyte?1,000,000 bytes or 100Kb
- 7How many Megabytes in a Gigabyte?1000MB
- 8How many Gigabytes in a Terabyte?1000GB
- 9What is the most signifcant bit?The bit with the largest value
- 10What is the least significant bit?The bit with the smallest value
- 11How many numbers can 1 byte represent?between 0 and 255 numbers
- 12How can we calculate the number of numbers an amount of bits can represent?2^n - 1
n= number of bits - 13What is hexadecimal?A hex or number system that uses base 16
- 14How does hexadecimal work?It uses 0-9 and then the letters A-F
A = 10
B = 11
C = 12
D = 13
E = 14
F = 15 - 15How can you convert hexadecimal to decimal?Multiply the left hand digit by 16 and then add the units
- 16How can you convert binary to hex?Split the binary value into 2 nibbles convert each nibble into its hex value and rejoin
- 17Why do programmers use hex?-It is much simpler to remember
- It is quicker to write and type
- People are less likely to make an error with fewer digits - 18What are the rules of binary addition?0 + 0 = 0
1 + 0 = 1
1 + 1 = 0 carry 1
1 + 1 + 1 = 1 carry 1 - 19What is an overflow error?When the result of the addition is too large for the number of bits the computer works with
- 20What does a left shift do to a number?Multiplies the number (by 2 if it is a single shift)
- 21What does a right shift do?Divides the number (by 2 if it is a single shift)
- 22What filetypes are used to store images?- jpeg
- png
- gif
- heic
- bmp - 23What are bitmap images made up of?Picture elements or pixels
- 24What is a pixel?The smallest identifiable area of an image. Each pixel is a single colour and is given a binary value which represents that colour
- 25What is image resolution?The concentration of pixels within a specific area. It is defined by multiplying the number of pixels in width and height of the image.
eg - 1920 x 1080 - 26What is bit/colour depth?The number of colours that can be represented. A pixel is attributed a number of bits the more bits the greater the colour depth
- 27What is metadata?data about data, information other than image data stored in a file such as the date created or the author
- 28How do you calculate image size?size in bits = width x height x colour depth
size in bytes = width x height x colour depth /8 - 29Describe analogue sound and digital soundAnalogue sound is continuous
Digital sound is discrete (sounds waves are sampled at regular intervals)
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- GCSE Computing (Data representation ) Flashcards on Data rep flashcards, created by Camryn Palmer on 15/10/2022.
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- Camryn Palmer
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