Logic circuits

When is the output of a two-input NOR gate 1?

  1. AWhen both inputs are 1
  2. BWhen the two inputs are different
  3. CWhen both inputs are 0
Show answer and explanation

Answer: C. When both inputs are 0

NOR is the negation of OR. OR outputs 0 only when all inputs are 0, so NOR outputs 1 only when all inputs are 0. As with NAND, any logic circuit can be built from NOR gates alone.

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More Logic circuits questions

  1. What is the simplified result of the expression A + A·B?
  2. What is an advantage of a synchronous circuit, in which all flip-flops operate on a common clock?
  3. In a synchronous circuit, what determines the maximum clock frequency at which it can operate?
  4. In a combinational circuit, what is the unwanted pulse that appears briefly at the output when an input changes, due to different delays along different paths?
  5. When is the output of a 2-input AND gate 1?