AQA AS Computing: 7.1 Logic gates and Boolean algebra

Question 1

Boolean Variable

Answer 1

A variable that may have two discrete possible values, e.g. true or false

Question 2

Truth Table

Answer 2

A table that shows the result of applying the logical function to all possible combinations of inputs

Question 3

OR Function

Answer 3

The output is true if either or both inputs are true

Question 4

AND Function

Answer 4

The output is true if all inputs are true

Question 5

NOT Function

Answer 5

The output is the inverse of the input

Question 6

Boolean Equation

Answer 6

An equation that expresses a Boolean output Q in terms of Boolean inputs X, Y, Z etc, to which one or more Boolean functions (such as OR, AND and NOT) are applied

Question 7

Logic Gate

Answer 7

An electronic circuit that performs a Boolean function

Question 8

Exclusive OR Function

Answer 8

The output is true if either input is true but not if both inputs are true

Question 9

NAND Function

Answer 9

The output is true is any input is false

Question 10

NOR Function

Answer 10

The output is true only when all inputs are false

Question 11

Today, what types of logic gates are processors made up of?

Answer 11

They are made up of NAND gates and NOR gates

Question 12

De Morgan’s Laws

Answer 12

A OR B = NOT(NOT A AND NOT B) / A AND B = NOT(NOT A AND NOT B)