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02 - Truth tables and logic circuits

 1. The concept may be confusing at first but all digital circuits are created using a combination of logic _______________
Learning note: 
==============
>>Electronic gates require a power supply.

>>Gate INPUTS are driven by voltages having two nominal values, e.g. 
0V and 5V representing logic 0 and logic 1 respectively.

>>The OUTPUT of a gate provides two nominal values of voltage only, 
e.g. 0V and 5V representing logic 0 and logic 1 respectively. 

>>In general, there is only one output to a logic gate except in some 
special cases.There is always a time delay between an input being 
applied and the output responding.

  mates

  CPUs

  gates

  bulbs

 2. The functionality of each gate can be described using a ________________
The structure used to represent the boolean expression 
of a logic gate function is commonly called a ___________.

A logic gate ____________shows each possible input combination
to the gate or circuit with the resultant output depending upon
the combination of these input(s).

  mathematical formula

  truth table

  logical deduction using english statements

  binary tree

 3. The following gate is an '_______' gate.
orgate.gif

  AND

  NAND

  NOT

  OR

 4. The NOT gate is an electrical circuit that produces an _______ version of the input as the output. (e.g. a 1 will be a 0)

  negative

  inverted

  positive

  converted

 5. A truth table can show the operations (with inputs and outputs) of any given gates. The following shows the truth table for the ________
2 Input truth table for an ____gate
======================
A      B      Output
------------------------
0       0            0
0       1            0                                   1       0            0       
1       1            1

  This truth table is incorrect and doesn't describe any gate

  Or Gate because when either A or B inputs are 1 the output is 1

  NOT Gate - because the output is always the inversion (opposite) of what is in A or B

  And Gate because both inputs (A and B) need to be 1 in order for the output to be 1

 6. Digital systems are said to be constructed by using logic gates. These gates are the AND, OR, NOT, NAND, NOR, EXOR and EXNOR gates.
allgates.png

  FALSE

  TRUE

 7. The following gate is an '_______' gate.
andgate.gif

  NOT

  OR

  NAND

  AND

 8. The following gate is an '_______' gate.
orgate.gif

  AND

  OR

  NAND

  NOT

 9. The following gate is an '_______' gate.
notgate.gif

  NOT

  OR

  NAND

  AND

 10. The AND gate is an electrical circuit that gives an output of ____ only if all of its inputs are also _____.

  1

  0

  3

  2

 11. The OR gate is an electrical circuit that gives an output of a 1 if_______________ of its inputs are a 1.

  none

  at least two

  all

  at least one

 12. If the input into a NOT gate is a 0 the output will also be a 0.

  FALSE

  TRUE

 13. Operations carried out by a NOT gate are also known as:

  reverting

  oppositing

  inverting

  opposing

 14. A logic gate in which the output is zero for inputs in which one input is one and other input is zero is likely to be:

  a FOR gate

  a NOT gate

  an OR gate

  an AND gate

 15. This is a table used to show possible combination of inputs for a specific output

  Truth Table

  Gate Table

  False Table

  Logic Table