Binary Basics
Convert the binary number 0000 1010 to denary.
10
How many bits are represented by one hexadecimal digit?
4 bits
What happens to a binary number when you logically shift it left by one place?
Its value is multiplied by 2.
What is the range of an 8-bit two's complement number?
−128 to 127
What is a character set?
A list/table of characters that a computer can represent, each with a unique binary code.
Convert 0010 1010 to denary.
42
Convert hexadecimal 2F to denary.
47
What happens to a binary number when you logically shift it right by one place?
Its value is divided by 2.
What is the purpose of using two's complement?
To represent/store negative numbers.
How many bits are used per character in extended ASCII?
8 bits
Convert 45 to an 8-bit binary number.
0010 1101
Convert binary 1100 1010 to hexadecimal.
CA
Perform a logical left shift of 2 places on 0000 0110.
0001 1000
Convert 1111 1011 using 8-bit two's complement to denary.
-5
Why was Unicode introduced?
ASCII cannot represent the thousands of characters, languages and symbols needed worldwide.
Convert 200 to an 8-bit binary number.
1100 1000
Convert hexadecimal B7 to 8-bit binary.
1011 0111
Add 0010 1101 + 0100 0110.
0111 0011
In the colour code #FF0000, what are the Red, Green and Blue values?
R = 255, G = 0, B = 0
What is colour depth?
The number of bits used per pixel to represent its colour.
What is the largest unsigned denary number that can be represented using 8 bits?
255
Give one reason hexadecimal is used instead of writing long binary numbers.
It is shorter/easier to read and less error-prone.
What happens when 1111 1111 + 0000 0001 is calculated using 8 bits?
0000 0000 — overflow occurs because 256 cannot be represented in 8 bits.
What colour is represented by #FF0000?
Pure red
What is the difference between lossy and lossless compression?
Lossy permanently removes data; lossless reduces file size without losing data and can recreate the original exactly.