Question 1: Fill in the truth table for the AND gate with two inputs A and B. Complete the table below: | A | B | Output | |---|---|---------| | 0 | 0 | | | 0 | 1 | | | 1 | 0 | | | 1 | 1 | |

Answer: A AND B is only true (1) when both A and B are true (1). | A | B | Output | |---|---|---------| | 0 | 0 | 0 | | 0 | 1 | 0 | | 1 | 0 | 0 | | 1 | 1 | 1 |

Question 2: Draw the logic circuit for an OR gate with two inputs labeled A and B. Label the circuit clearly.

Answer: A correct sketch would show a standard OR gate symbol with two input lines labeled A and B entering the gate, and an output line emerging from the gate.

Question 3: Complete the truth table for the NOT gate with input A. Fill in the output column: | A | Output | |---|--------|

Answer: NOT A outputs the opposite of A. | A | Output | |---|--------| | 0 | 1 | | 1 | 0 |

Question 4: Describe a simple digital circuit that uses an AND gate and a NOT gate to produce an output that is true only when A is true and B is false. Do not draw, just explain verbally.

Answer: The circuit has input A connected directly to an AND gate, input B connected to a NOT gate, and the output of the NOT gate connected to the second input of the AND gate. The output of the AND gate is true only when A is true and B is false.

Question 5: Write the Boolean expression for a circuit that outputs true only when either A is true or B is true, but not both.

Answer: A XOR B (exclusive OR)

Question 6: Draw a truth table for the XOR gate with inputs A and B. Label the output column clearly.

Answer: A correct truth table for XOR: | A | B | Output | |---|---|---------| | 0 | 0 | 0 | | 0 | 1 | 1 | | 1 | 0 | 1 | | 1 | 1 | 0 |

Question 7: Explain in your own words what a Boolean variable is and give an example relevant to digital devices.

Answer: A Boolean variable is a variable that can only have two possible values: true (1) or false (0). For example, a variable could represent whether a door is open (true) or closed (false).

Question 8: Sketch a simple logic circuit that uses an AND gate and a NOT gate to implement the Boolean expression A AND (NOT B). Label all inputs, gates, and output.

Answer: A correct sketch would show input A going directly into an AND gate. Input B goes into a NOT gate, and the output of the NOT gate connects to the second input of the AND gate. The output of the AND gate is the final output.

Question 9: Complete the truth table for a NAND gate with inputs A and B. Fill in the output column:

Answer: NAND is the opposite of AND. | A | B | Output | |---|---|---------| | 0 | 0 | 1 | | 0 | 1 | 1 | | 1 | 0 | 1 | | 1 | 1 | 0 |

Question 10: Describe a real-world example where a Boolean logic gate might be used in a household device.

Answer: A household alarm system might use an AND gate to trigger the alarm only if two conditions are met, such as a door being open AND a security code being entered.