computing year 9

• what are the two possible binary digits?

  0, 1
• what letter does hexadecimal go up to?

  F
• finish the sentence. Hexadecimal is a base...?

  16
• what does bit stand for?

  binary digit
• Convert 11101 to a denary number. 

  29
• what do computers use binary for?

  to process data
• what does '1' mean in binary?

  on
• what does '0' mean in binary?

  off
• define binary.

  binary is a number system that only uses two digits, 0 and 1.
• the binary system is known as a base 2 system. Why?

  there are only 2 digits to select from and when using binary, data is converted by using the power of 2.
• What are digital images made up of?

  pixels
• Each pixel in an image is made up of what?

  binary numbers.
• To create a picture, a grid is set out and the pixels assigned a binary code but before the grid can be created what needs to be known first?

  the size of the grid.
• what is metadata?

  data about data.
• why do computers need metadata?

  to know the size of an image.
• define the resolution of an image.

  a way of describing how tightly packed the pixels are.
• what is the formula for resolution?

  width*height in pixels.
• Is high resolution better or worse?

  better.
• What does it mean when an image has a higher resolution?

  That it closer to the original (less blurry).
• If an image has a low resolution, is it storing more or less data?

  less data.
• what is the colour depth?

  The number of bits used to represent the color of a single pixel in a digital image.
• Fill in the blank spaces. A ... colour depth means ... colours are available

  higher, more
• What does pixelated mean? 

  Pixelated means that you are able to see the pixels when the image in enlarged. 
• What does sample rate mean?

  How many samples of data are taken per second.
• What is sample rate usually measured in?

  hertz.
• what are digital images made up of?

  pixels.
• what make up pixels?

  binary numbers.