EEE 120 Quiz 1 Requires Respondus LockDown Browser +
Webcam Q&A | Graded A+ | Fall Update 2026-2027
1. Which of the following best describes the function of an AND gate?
A) Outputs 1 only when all inputs are 1
B) Outputs 1 when at least one input is 1
C) Outputs the inverse of the input
D) Outputs 1 only when an odd number of inputs are 1
Correct Answer: Outputs 1 only when all inputs are 1
Rationale: An AND gate produces a high output (1) only when all of its inputs are high (1). If any
input is low (0), the output is low. This is the fundamental definition of the AND logic function.
The OR gate outputs 1 when at least one input is 1, the NOT gate inverts the input, and the XOR
gate outputs 1 for an odd number of 1 inputs.
2. What is the primary function of a NOT gate?
A) Inverting the input signal
B) Performing addition of two binary numbers
C) Outputting 1 only when both inputs are 1
D) Storing a single bit of data
Correct Answer: Inverting the input signal
Rationale: A NOT gate, also called an inverter, produces an output that is the logical
complement of its input. If the input is 0, the output is 1; if the input is 1, the output is 0. It does
not perform arithmetic, act as an AND gate, or store data.
3. Which logic gate is functionally complete on its own?
A) AND
B) OR
C) NAND
D) XOR
Correct Answer: NAND
Rationale: A functionally complete set of logic gates can be used to implement any Boolean
function. The NAND gate is functionally complete because any other logic gate (AND, OR, NOT)
can be constructed using only NAND gates. The AND, OR, and XOR gates are not functionally
complete on their own.
, 4. Which of the following is the correct truth table for a NOR gate?
A) Output is 1 only when both inputs are 0
B) Output is 1 when at least one input is 1
C) Output is 1 only when both inputs are 1
D) Output is 1 when inputs are different
Correct Answer: Output is 1 only when both inputs are 0
Rationale: A NOR gate is the inverse of an OR gate. The output is 1 only when all inputs are 0. If
any input is 1, the output is 0. The OR gate outputs 1 when at least one input is 1, and the AND
gate outputs 1 only when all inputs are 1.
5. How many distinct input combinations exist for a 3-input logic gate?
A) 3
B) 6
C) 8
D) 9
Correct Answer: 8
Rationale: For a logic gate with n inputs, there are 2^n possible input combinations. For 3
inputs, 2^3 = 8 combinations, ranging from 000 to 111. The number of distinct combinations is
not 3, 6, or 9.
6. What is the primary purpose of a truth table?
A) To show the output of a logic circuit for every possible input combination
B) To calculate the power consumption of a digital circuit
C) To determine the physical layout of a circuit board
D) To measure the propagation delay of a gate
Correct Answer: To show the output of a logic circuit for every possible input combination
Rationale: A truth table is a systematic way of listing all possible input combinations and the
corresponding output for a logic function. It does not measure power, determine physical
layout, or measure timing. It is a fundamental tool for analyzing and designing combinational
logic.
7. Which of the following gates outputs 1 when an odd number of inputs are 1?
A) XOR
B) XNOR
C) AND
D) NAND
, Correct Answer: XOR
Rationale: The XOR (exclusive-OR) gate outputs 1 when the number of high inputs is odd. For a
2-input XOR, this means the output is 1 when the inputs are different. XNOR outputs 1 when
the number of high inputs is even. AND and NAND do not have this property.
8. What is the decimal equivalent of the binary number 1011?
A) 9
B) 11
C) 13
D) 15
Correct Answer: 11
Rationale: To convert binary 1011 to decimal, calculate (1 × 2^3) + (0 × 2^2) + (1 × 2^1) + (1 ×
2^0) = 8 + 0 + 2 + 1 = 11. The other options are incorrect conversions.
9. Convert the hexadecimal number 2F to decimal.
A) 31
B) 47
C) 63
D) 95
Correct Answer: 47
Rationale: In hexadecimal, 2F equals (2 × 16^1) + (15 × 16^0) = 32 + 15 = 47. The letter F
represents 15 in hexadecimal. The other options do not match this conversion.
10. What is the binary representation of the decimal number 25?
A) 11001
B) 10101
C) 11010
D) 10011
Correct Answer: 11001
Rationale: To convert 25 to binary, repeatedly divide by 2: 25 ÷ 2 = 12 remainder 1, 12 ÷ 2 = 6
remainder 0, 6 ÷ 2 = 3 remainder 0, 3 ÷ 2 = 1 remainder 1, 1 ÷ 2 = 0 remainder 1. Reading the
remainders upward gives 11001. The other options represent different decimal values.
11. What is the 8-bit two's complement representation of the decimal number -40?
A) 11011000
B) 10101000
Webcam Q&A | Graded A+ | Fall Update 2026-2027
1. Which of the following best describes the function of an AND gate?
A) Outputs 1 only when all inputs are 1
B) Outputs 1 when at least one input is 1
C) Outputs the inverse of the input
D) Outputs 1 only when an odd number of inputs are 1
Correct Answer: Outputs 1 only when all inputs are 1
Rationale: An AND gate produces a high output (1) only when all of its inputs are high (1). If any
input is low (0), the output is low. This is the fundamental definition of the AND logic function.
The OR gate outputs 1 when at least one input is 1, the NOT gate inverts the input, and the XOR
gate outputs 1 for an odd number of 1 inputs.
2. What is the primary function of a NOT gate?
A) Inverting the input signal
B) Performing addition of two binary numbers
C) Outputting 1 only when both inputs are 1
D) Storing a single bit of data
Correct Answer: Inverting the input signal
Rationale: A NOT gate, also called an inverter, produces an output that is the logical
complement of its input. If the input is 0, the output is 1; if the input is 1, the output is 0. It does
not perform arithmetic, act as an AND gate, or store data.
3. Which logic gate is functionally complete on its own?
A) AND
B) OR
C) NAND
D) XOR
Correct Answer: NAND
Rationale: A functionally complete set of logic gates can be used to implement any Boolean
function. The NAND gate is functionally complete because any other logic gate (AND, OR, NOT)
can be constructed using only NAND gates. The AND, OR, and XOR gates are not functionally
complete on their own.
, 4. Which of the following is the correct truth table for a NOR gate?
A) Output is 1 only when both inputs are 0
B) Output is 1 when at least one input is 1
C) Output is 1 only when both inputs are 1
D) Output is 1 when inputs are different
Correct Answer: Output is 1 only when both inputs are 0
Rationale: A NOR gate is the inverse of an OR gate. The output is 1 only when all inputs are 0. If
any input is 1, the output is 0. The OR gate outputs 1 when at least one input is 1, and the AND
gate outputs 1 only when all inputs are 1.
5. How many distinct input combinations exist for a 3-input logic gate?
A) 3
B) 6
C) 8
D) 9
Correct Answer: 8
Rationale: For a logic gate with n inputs, there are 2^n possible input combinations. For 3
inputs, 2^3 = 8 combinations, ranging from 000 to 111. The number of distinct combinations is
not 3, 6, or 9.
6. What is the primary purpose of a truth table?
A) To show the output of a logic circuit for every possible input combination
B) To calculate the power consumption of a digital circuit
C) To determine the physical layout of a circuit board
D) To measure the propagation delay of a gate
Correct Answer: To show the output of a logic circuit for every possible input combination
Rationale: A truth table is a systematic way of listing all possible input combinations and the
corresponding output for a logic function. It does not measure power, determine physical
layout, or measure timing. It is a fundamental tool for analyzing and designing combinational
logic.
7. Which of the following gates outputs 1 when an odd number of inputs are 1?
A) XOR
B) XNOR
C) AND
D) NAND
, Correct Answer: XOR
Rationale: The XOR (exclusive-OR) gate outputs 1 when the number of high inputs is odd. For a
2-input XOR, this means the output is 1 when the inputs are different. XNOR outputs 1 when
the number of high inputs is even. AND and NAND do not have this property.
8. What is the decimal equivalent of the binary number 1011?
A) 9
B) 11
C) 13
D) 15
Correct Answer: 11
Rationale: To convert binary 1011 to decimal, calculate (1 × 2^3) + (0 × 2^2) + (1 × 2^1) + (1 ×
2^0) = 8 + 0 + 2 + 1 = 11. The other options are incorrect conversions.
9. Convert the hexadecimal number 2F to decimal.
A) 31
B) 47
C) 63
D) 95
Correct Answer: 47
Rationale: In hexadecimal, 2F equals (2 × 16^1) + (15 × 16^0) = 32 + 15 = 47. The letter F
represents 15 in hexadecimal. The other options do not match this conversion.
10. What is the binary representation of the decimal number 25?
A) 11001
B) 10101
C) 11010
D) 10011
Correct Answer: 11001
Rationale: To convert 25 to binary, repeatedly divide by 2: 25 ÷ 2 = 12 remainder 1, 12 ÷ 2 = 6
remainder 0, 6 ÷ 2 = 3 remainder 0, 3 ÷ 2 = 1 remainder 1, 1 ÷ 2 = 0 remainder 1. Reading the
remainders upward gives 11001. The other options represent different decimal values.
11. What is the 8-bit two's complement representation of the decimal number -40?
A) 11011000
B) 10101000
