6. NAND-NAND circuits are equivalent to—

1. 1. AND-OR circuits

   
   
   

   2. OR-XOR circuits
      

   
   
   

   3. OR-NOT circuits

   
   
   

   4. All of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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7. Find (177)₈ + 1, in decimal—

1. 1. 128

   
   
   

   2. 200

   
   
   

   3. 178

   
   
   

   4. 179

   
   
   

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1. View Hint View Answer Discuss in Forum

   (177)₈:
   1 × 8² + 7 × 8 + 7 = (127)₁₀
   127 + 1 = 128

   Correct Option: A

   (177)₈:
   1 × 8² + 7 × 8 + 7 = (127)₁₀
   127 + 1 = 128

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8. According to De Morgan’s second theorem—

1. 1. A NAND gate is always complimentary to an AND gate

   
   
   

   2. An AND gate is equivalent to a bubbled NAND gate

   
   
   

   3. A NAND gate is equivalent to a bubbled AND gate

   
   
   

   4. A NAND gate is equivalent to a bubbled OR gate

   
   
   

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1. View Hint View Answer Discuss in Forum

   
   Hence alternative (D) is the correct answer.
   

   Correct Option: D

   
   Hence alternative (D) is the correct answer.
   

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9. Identify the operation performed by the gate circuit shown in figure—
   

1. 1. AND

   
   
   

   2. OR

   
   
   

   3. NAND

   
   
   

   4. NOR

   
   
   

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1. View Hint View Answer Discuss in Forum

   
   Y = [(AB)′]′ = AB i.e., equivalent to AND gate. Hence alternative (A) is the correct answer.

   Correct Option: A

   
   Y = [(AB)′]′ = AB i.e., equivalent to AND gate. Hence alternative (A) is the correct answer.

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10. The output of a gate is 1 if and only if all the inputs of that gate are high, what is that gate?

1. 1. NOT

   
   
   

   2. NAND

   
   
   

   3. NOR

   
   
   

   4. AND

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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