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07 - XOR, NAND and NOR Gates

 1. Which of the following statements are true?
Statement 1:
=============
Boolean functions may be practically implemented by using 
electronic gates

Statement 2:
==============
There is always a time delay between an input being applied 
and the output responding.

  Just statement 2

  Both statements 1 and 2

  Neither statements 1 or 2 are true (both are false)

  Just statement 1

 2. The XOR gate (sometimes EOR, or EXOR and pronounced as Exclusive OR) is a gate that gives a true (1 or HIGH) output when ______________________

  the number of true inputs is even

  the number of true inputs is odd.

  the number of false inputs is odd

  the number of false inputs is even

 3. Another way of putting it is: An XOR gate implements an exclusive or; that is, a true output results, if _____________________

  both and only both of the inputs to the gate is true

  one, and only one, of the inputs to the gate is either true or false

  one, and only one, of the inputs to the gate is true.

  both inputs are false

 4. XOR represents the ____________, - "one or the other but not both". (both cannot be the same)

  trueness function

  falseness function

  inequality function

  equality function

 5. Analyse the truth table in the image below. What gate are we dealing with here?
truthtableforwhatgate_guess.png

  OR

  NOR

  XOR

  NAND

 6. ____can also be viewed as addition modulo 2. As a result,____ gates are used to implement binary addition in computers.

  NAND

  OR

  NOR

  XOR

 7. A _______ gate is an inverted AND gate and is also a universal gate (other gates can be represented as a combination of _____ gates)

  NAND

  OR

  XOR

  NOR

 8. A NOR gate is an OR gate with an inverted output. Output is high when ____________________

  either input A or input B is high

  both input A and input B are high

  neither input A nor input B is high

  just input A is high

 9. Four NAND gates have been connected together as shown to produce a ______________ gate
fournandgates.png

  OR

  XOR

  NOR

  NAND

 10. A _____ gate is a logic gate which gives a positive output only when both inputs are negative

  NAND

  OR

  XOR

  NOR

 11. What is thought to be the first embedded system - the Apollo Guidance Computer, was built exclusively from ____ gates, about 5,600 in total for the later versions
The Apollo Guidance Computer (AGC) was a digital computer produced
 for the Apollo program that was installed on board each Apollo 
Command Module (CM) and Lunar Module (LM). The AGC provided computation 
and electronic interfaces for guidance, navigation, and control of the 
spacecraft.
apolloguidancecomputer.png

  XOR

  NOR

  OR

  NAND

 12. The following truth table is likely to be for a:
INPUT	OUTPUT
A	B	A ___? B
=========================
0	0	  1
0	1	  0
1	0	  0
1	1	  0

  XOR gate

  NAND gate

  NOR gate

  MORE gate

 13. In an XOR gate, when both inputs A and B are zero, output will be

  1

  previous value

  0

  default

 14. Logically, the output of a NOR gate would have the same Boolean expression as a(n):

  AND gate immediately followed by an inverter

  NOR gate immediately followed by an inverter

  OR gate immediately followed by an inverter

  NAND gate immediately followed by an inverter

 15. From the truth table for a three-input NOR gate, what is the only condition of inputs A, B, and C that will make the output X high?

  A = 0, B = 0, C = 1

  A = 0, B = 0, C = 0

  A = 1, B = 1, C = 1

  A = 1, B = 0, C = 0

 16. The output of a NAND gate is LOW if ________.

  all inputs are LOW

  all inputs are HIGH

  any input is LOW

  any input is HIGH

 17. The truth table in this image shows that the NOR gate output is the ___________ of the OR gate output for all possible input conditions.
NORgatediagram.png

  double

  exact duplicate

  exact inverse

  exact same

 18. By coupling a NOT gate with the output terminal of an AND gate, we get

  a NAND gate

  an OR gate

  an AND gate

  a NOR gate

 19. The symbol for a NAND gate is an AND gate with a small circle on the output. The small circle represents inversion.

  FALSE

  TRUE

 20. The NAND and _________ gates are called universal functions/gates since with either one the AND and OR functions and NOT can be generated.

  XAND

  NOR

  XOR

  NOT