# 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? 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 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.``` 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. 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