Logic gates and logic circuits

Cambrdige AS level computer science 2025. Textbook references: Cambridge International AS and A level computer science coursebook Sylvia Langfield, David Duddell 2019 press ||| Cambrdige International AS and A Levels Computer science by David Wastson, Helen Williams press 2019

what is this gate?

NOT

what is this gate?

AND

what is this gate?

OR

what is this gate?

NAND

what is this gate?

NOR

what is this gate?

XOR

If the input is 0 for a NOT gate, what is the output

1

if the input for a NOT gate is 1, what is the output

0

is the input is 00 for a AND gate, What is the output?

0

is the input is 00 for a OR gate, What is the output?

0

is the input is 00 for a NAND gate, What is the output?

1

is the input is 00 for a NOR gate, What is the output?

1

is the input is 00 for a XOR gate, What is the output?

0

is the input is 1 0 for a AND gate, What is the output?

0

is the input is 1 0 for a OR gate, What is the output?

1

is the input is 1 0 for a NAND gate, What is the output?

1

is the input is 1 0 for a NOR gate, What is the output?

0

is the input is 1 0 for a XOR gate, What is the output?

1

is the input is 1 1 for a AND gate, What is the output?

1

is the input is 1 1 for a OR gate, What is the output?

1

is the input is 1 1 for a NAND gate, What is the output?

0

is the input is 1 1 for a NOR gate, What is the output?

0

is the input is 1 1 for a XOR gate, What is the output?

0

what is a transistor

semicondiuctor device used to aplify or swith electronic signals and electrical power

what is a transistor semiconducter composed of

material usually with at least three terminals for connection to an external circut

what is the Boolean expression for the AND gate

A x B

what is the Boolean expression for the OR gate

A + B

what is a logical diagram

a graphical representation of a circuit

what is a truth table

defines the function of a gate or circuit bu listing all possible input combinations that the gate or circuit could encountrer

what is a logic gate

a component of a logical circuit that has an operation matching that of a boolean operator

what is logic proposition

a statement that is either TRUE or FALSE

what is a problem statement

an informal definition of an outcome which is dependent on one logic proposition or a combination of two or more logical propositions

which gate is if input is 1 then the output is 1

OR

which gate gives 0 output when both inputs are 1

NAND

which gate gives 1 output only when both inputs are 0

NOR

which gate produces 0 if its two inputs are the same

XOR

what does N represent at the beginning of logic gate names

NOT

what does X represent in logic gates

exclusive

what is a logic expression

logic propositions combined using Boolean operatiors, which may be equated to a defined outcome

what represents any logic expression or describe the possible outputs from a logic circuit

truth tables

what are the three boolean operatiors

AND, OR, NOT

what is the boolean operation you would use for this phrase?: you should take an umbrella if it is raining or if the weather forcasts for rain later

OR

what is the boolean operation you would use for this phrase?: the air-conditioning system is set to come on in an office only during working hours but also only if the temperature rises above 25 degrees

AND

what are boolean logic values

TRUE or FALSE

how can you tell a logic gate is different from another

the shape of the symbol

do all logic gates take 2 inputs?

no

do all logic gates output 1 value?

yes

is the number of inputs limited to two

no

where do you input values for a logic gate

left

where do you output values for a logic gate

right

which logic gate only takes one input

NOT

what is a logic circuit

a bunch of logic gates leading to one value

what symbol matches this truth table?

NOT

what symbol matches this truth table?

AND

what symbol matches this truth table?

OR

what symbol matches this truth table?

NAND

what symbol matches this truth table?

NOR

what symbol matches this truth table?

XOR

what does X represent at the beginning of logic gate name XOR

exclusive

what is boolean algebra

a form of algebra linked to logic circuites and based on TRUE and FALSE

how many posiible outputs are possible from two inputs

4

how many possible outputs are possible from three inputs

8

what takes binrary inputs to produce a binary output

logic gates

what is the logic notation for: NOT

NOT A

what is the logic notation for: AND

A AND B

what is the logic notation for: OR

A OR B

what is the logic notation for: NAND

A NAND B

what is the logic notation for: NOR

A NOR B

what is the logic notation for: XOR

A XOR B

what is the boolean algebra for: NOT

Ā

what is the boolean algebra for: AND

A . B

what is the boolean algebra for: OR

A + B

what is the boolean algebra for: NAND

A . B (Line on top)

what is the boolean algebra for: NOR

A + B (line on top)

which logic gates matches with this boolean algebra: (A . B(line on B)) + (A . B(line on A))

XOR

which logic gate matches with the boolean algebra: (A + B) . A . B(line on top))

XOR

what logic gate does a dot represent

AND

what logic gate does + represent

OR

what logic gate does a dash/line above the lettter represent

NOT

what are logic “building blocks“

fundamental components used to construct digital logic circuits.

complex question, what logic gate do these make when put together?: two NAND gates

AND

complex question, what logic gate do these make when put together?: two NAND gates into one NAND gate

OR

complex question, what logic gate do these make when put together?: same value into NAND gate

NOT

how do you simplify a logic circuit

reduce the number of components

why is it good to reduce the number of components in a logic circuit

const of production becomes less

what is a multi-input logic gate

digital logic gate that accepts three or more input signals to perform Boolean operations.

what should you keep in mind when constructing a truth table

far left colums for input and written with increasing binary values

what is the best approach when constructing a logic circuit from a problem statement

convert into a logic expression

when writing a logic expression with a lot of problem statements, how do brackets help

ensure that the meaning is clear and seperates each logic gate to make it easier to draw