Computer Science for IGCSE & O level - Boolean Logic (Section 7)

  • 1
    What type of gate is created by inverting the output of a NOR gate?
    Svare
    (B)
    OR gate
  • 2
    The Boolean expression for an OR gate with inputs A and B is:
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    (B)
    A + B
  • 3
    If, in a half adder, A=1 and B=1, what are the values of Sum and Carry?
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    (B)
    Sum = 0, Carry = 1
  • 4
    In a logic circuit, the symbol '¬' or an overbar on a variable represents which operation?
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    (C)
    NOT
  • 5
    In digital logic, the output of a gate is usually represented as:
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    (C)
    Binary values
  • 6
    What is the result of the Boolean expression A + 0?
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    (C)
    A
  • 7
    What type of gate is created by inverting the output of an OR gate?
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    (C)
    NOR
  • 8
    How many inputs are required to generate a full adder circuit?
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    (C)
    3
  • 9
    Which logic gate outputs a 1 if any of the inputs is 1?
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    (B)
    OR
  • 10
    What is the output of a NAND gate if the inputs are 1 and 0?
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    (B)
    1
  • 11
    What logic operation is represented by the symbol ‘+’ in Boolean algebra?
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    (B)
    OR
  • 12
    What is the output of an XOR gate if the inputs are 0 and 1?
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    (B)
    1
  • 13
    Which logical operations does an AND gate perform?
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    (B)
    Outputs 1 only if all inputs are 1; otherwise 0.
  • 14
    Which gate's output is HIGH (1) if *any* of its inputs are HIGH?
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    (B)
    OR
  • 15
    Which of these gates is considered to be the complement of an OR gate?
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    (C)
    NOR
  • 16
    What logic gate combines the functions of AND and NOT?
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    (B)
    NAND gate
  • 17
    If A = 1 and B = 1, what is the output of a NAND gate?
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    (A)
    0
  • 18
    What does the term 'truth table' represent in digital electronics?
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    (B)
    A table showing the output of a gate for all input combinations
  • 19
    What is the result of the Boolean expression A . A'?
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    (A)
    0
  • 20
    What type of gate produces an output HIGH (1) only if the inputs are different?
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    (C)
    XOR
  • 21
    If the inputs to an AND gate are A=1 and B=1, what is the output?
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    (B)
    1
  • 22
    What is the fundamental operation of a NOT gate?
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    (B)
    Inversion
  • 23
    A logic gate with two inputs produces a HIGH (1) output only when both inputs are LOW (0). What type of gate is it?
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    (C)
    NOR
  • 24
    Which of the following is the symbol for the AND gate?
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    (B)
    ·
  • 25
    What is the function performed by a NOT gate?
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    (B)
    Inverts the input signal
  • 26
    Which of the following are the correct ways to describe the function of a logic gate?
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    A
    B
    C
  • 27
    Which of the following correctly describes the output of a 2-input XOR gate?
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    (C)
    Output is 1 if the inputs are different
  • 28
    What is the definition of a 'logic circuit'?
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    (B)
    A circuit that uses logic gates to perform operations on binary inputs.
  • 29
    What does the term 'half adder' refer to?
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    (A)
    A logic circuit that adds two single binary digits.
  • 30
    What is the output of an XOR gate if the inputs are 1 and 1?
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    (A)
    0
  • 31
    What is the main function of the half adder circuit?
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    (C)
    Adding two binary numbers
  • 32
    What output is produced by a NOR gate if both inputs are 1?
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    (A)
    0
  • 33
    Which one is a fundamental part of a digital computer?
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    (A)
    Logic gates
  • 34
    If an input signal to a NOT gate is HIGH, what is the output signal?
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    (B)
    LOW
  • 35
    In Boolean algebra, what does the complement of a variable represent?
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    (B)
    The inverse or NOT operation
  • 36
    What is the output of a 2-input NOR gate if A = 1 and B = 0?
    Svare
    (A)
    0
  • 37
    In a digital circuit, a NOT gate will change the state of a signal. What describes the state of a signal?
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    (B)
    The voltage level of the signal.
  • 38
    Which gate's output is HIGH if and only if all inputs are HIGH?
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    (A)
    AND
  • 39
    What is the output of a NOT gate if the input is HIGH (logic 1)?
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    (B)
    LOW (0)
  • 40
    Which gate outputs '1' if all inputs are '1'?
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    (A)
    AND
  • 41
    Which of the following gates is considered a 'universal' gate?
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    (C)
    NAND gate
  • 42
    Which gate's output is HIGH only when the inputs are different?
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    (C)
    XOR
  • 43
    Which of the following is equivalent to a XOR gate using only AND, OR, and NOT gates?
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    (B)
    (A AND NOT B) OR (NOT A AND B)
  • 44
    What is the function of the NOT gate?
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    (B)
    To invert the input signal.
  • 45
    What does the term 'truth table' represent in digital logic?
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    (D)
    A table showing all possible combinations of inputs and their corresponding outputs
  • 46
    In Boolean algebra, the OR operation is represented by which symbol?
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    (A)
    +
  • 47
    The full adder circuit is often built from:
    Svare
    (A)
    Two half adders and an OR gate
  • 48
    What is the output of an XNOR gate with inputs A=0 and B=1?
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    (A)
    0
  • 49
    What is the output of a 3-input OR gate when all inputs are 0?
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    (A)
    0
  • 50
    Which gate is used to change a 1 input to a 0 output?
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    (C)
    NOT gate