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Inputs given to a logic gate are A and B and its output is X. If A = 1, B = 0, then X = 1. What type of gate this could be?
  • a)
    OR
  • b)
    NAND
  • c)
    AND
  • d)
    NOR
Correct answer is option 'A,B'. Can you explain this answer?

Vaibhav Ghosh answered

 clearly it follows OR gate. 


Thus, it also follows NAND gate 
  it is an AND gate 
 it is not a NOR gate. 
Therefore, the correct options are (b, c)
The correct answers are: NAND, OR

If the output of a logic gate is 0 only when all its inputs are at logic 1, then which of the following are/is not the corresponding gate?
  • a)
    AND
  • b)
    NAND
  • c)
    NOR
  • d)
    NOT
Correct answer is option 'A,C,D'. Can you explain this answer?

Aarohi Shukla answered
AND gate:
- An AND gate produces an output of 1 only when all of its inputs are at logic 1. If any of the inputs are at logic 0, the output will be 0.
- Therefore, the output of an AND gate is 0 when all inputs are at logic 1, which matches the given condition. So, the AND gate is a corresponding gate.

NAND gate:
- A NAND gate produces an output of 0 only when all of its inputs are at logic 1. If any of the inputs are at logic 0, the output will be 1.
- Therefore, the output of a NAND gate is not 0 when all inputs are at logic 1, which does not match the given condition. So, the NAND gate is not a corresponding gate.

NOR gate:
- A NOR gate produces an output of 0 only when all of its inputs are at logic 1. If any of the inputs are at logic 0, the output will be 1.
- Therefore, the output of a NOR gate is not 0 when all inputs are at logic 1, which does not match the given condition. So, the NOR gate is not a corresponding gate.

NOT gate:
- A NOT gate produces an output that is the opposite of its input. If the input is 1, the output will be 0, and if the input is 0, the output will be 1.
- Therefore, the output of a NOT gate is always 0 when the input is 1, which matches the given condition. So, the NOT gate is a corresponding gate.

Based on the given condition, the corresponding gates are the AND gate and the NOT gate. The NAND gate and the NOR gate do not meet the condition because their outputs are not 0 when all inputs are at logic 1.

The binary number 110000111101 corresponds to a hexadecimal number. 
  • a)
    CFD
  • b)
    DBF 
  • c)
    D3C
  • d)
    C3D
Correct answer is option 'D'. Can you explain this answer?

Bhavana Pillai answered
Hexadecimal is written with 16 numbers starting from 0, i.e., 0, 1,2, 3,...14, 15. The number 10 → A; 11 → B; 12 → C; 13 → D; 14 → E; 15 → F in place of two digits. To convert binary number in hexadecimal make the pairs of four numbers starting from right. Then convert them in decimal then hexadecimal e.g. (110000111101) ⇔ [(1100) (0011) (1101)2] in binary number ⇔ [(12) (3) (13) ] in decimal
= C3D is the equivalent hexadecimal number
The correct answer is: C3D

The number 6.25 in the decimal notation, when converted to the binary notation will read as ?
    Correct answer is '110.01'. Can you explain this answer?

    Aashna Shah answered

    Hence, 6 =110
    Now 0.25 x 2 = 0.50 → 0
    0.50 x 2 = 1.00 → 1
    0.00 x 2 = 0 → 0
    Hence, 0.25 = 0.010 →1
    Hence (6.25)2 = 110.010
    The correct answer is: 110.01

    The minimum number of NAND gates required to implement ?
      Correct answer is '0'. Can you explain this answer?

      Vedika Singh answered

      Hence, minimum number of NAND gates required to implement
       is zero.
      The correct answer is: 0

      How many entries will be in the truth table of a 4-input NAND gate?
      • a)
        6
      • b)
        8
      • c)
        16
      • d)
        32
      Correct answer is option 'C'. Can you explain this answer?

      A NAND gate is a universal logic gate that performs the negation (NOT) of an AND logic operations in digital circuits. 
      As we know, 
      Y = 2
      Y number of Entries in the truth table Where, n = number of inputs.

      The Boolean expression   can be realized by how many minimum number of gates?
        Correct answer is '1'. Can you explain this answer?

        Sagarika Yadav answered

        Hence one two input AND gate is required.
        ∴ Minimum number of gate = 1.
        The correct answer is: 1

        The logic function is defined as:
        f = [(x AND y) OR (z AND NOT x)] AND [NOT (x XOR z)]
        Evaluate the output of the function for:
        • x = 1
        • y = 0
        • z = 1
        Correct answer is '0'. Can you explain this answer?

        Pie Academy answered
        Solution:
        • Step 1: Simplify the first part:
          • (x AND y):
          • x = 1, y = 0 → (x AND y) = 1 AND 0 = 0.
          • (z AND NOT x):
          • z = 1, NOT x = 0 → (z AND NOT x) = 1 AND 0 = 0.
          • (x AND y) OR (z AND NOT x):
          • 0 OR 0 = 0.
        • Step 2: Simplify the second part:
          • (x XOR z):
          • x = 1, z = 1 → (x XOR z) = 0 (since XOR is true only if inputs are different).
          • NOT (x XOR z) = NOT 0 = 1.
        • Step 3: Combine both parts:
          • f = [(x AND y) OR (z AND NOT x)] AND [NOT (x XOR z)]
          • f = 0 AND 1 = 0.
        Final Answer:
        The value of f is 0.

        In the given figure, circuit  performs the operation of :
        • a)
          AND gate for a positive logic system
        • b)
          OR gate for a negative logic system
        • c)
          NAND gate for a negative logic system
        • d)
          AND gate for a negative logic system
        Correct answer is option 'B'. Can you explain this answer?

        Sarthak Chavan answered
        If either V1 is positive or V2 is positive, V0 be positive, otherwise we get a low output for both V1 and V2 negative. Hence it acts as an OR gate.
        The correct answer is: OR gate for a negative logic system

        Which of the following sets of values given below satisfy the Boolean relation 
        • a)
          P = 0, Q = 0, R = 0
        • b)
          P = 1, Q = 0, R = 1
        • c)
          P = 1, Q = 1, R = 0
        • d)
          P = 1, Q = 1, R = 1
        Correct answer is option 'A,B,C'. Can you explain this answer?

        Vandana Chopra answered
        The realization of the algebraic expression   in terms of logic gate is

        Truth table.

        Hence, (a), (c), (d)
        The correct answers are: P = 0, Q = 0, R = 0, P = 1, Q = 0, R = 1, P = 1, Q = 1, R = 0

        What is the output for X = 1, Y = 0 for the logic circuit drawn below :
          Correct answer is '1'. Can you explain this answer?

          Preethi Joshi answered
          The truth table for the above circuit is.

          Hence, for X = 1, Y = 0, output = 1
          The correct answer is: 1 

          The following circuit  does not performs the operation of.
          • a)
            NAND gate for a negative logic system
          • b)
            AND gate for a positive logic system
          • c)
            AND gate for a negative logic system
          • d)
            OR gate for a negative logic system
          Correct answer is option 'A,B,C'. Can you explain this answer?

          Pranavi Mishra answered
          If either V1 or V2 is high, we get a high in output, hence it each like an OR gate.
          The correct answers are: NAND gate for a negative logic system, AND gate for a positive logic system, AND gate for a negative logic system

          The circuit shown in the figure below functions as
          • a)
            AND gate
          • b)
            NAND gate 
          • c)
            OR gate 
          • d)
            NOR gate
          Correct answer is option 'C'. Can you explain this answer?

          Partho Gupta answered
          When A is high and B is low i.e. A = 1, B = 0 transistor A conducts and Y becomes high, i.e. Y = 1. If A = 0 and B = 1; transistor B conducts Y = 1, if A = 1 and B = 1; both transistors conduct. If A = B = 0. None of the transistors conducts hence Y= 0. The true table is shown below.

          The correct answer is: OR gate

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