Logic Gates and Truth Tables Quiz Quiz

Explore the essential concepts of logic gates and their corresponding truth tables. This quiz helps learners assess and reinforce their understanding of basic digital logic operations and how they are represented in truth tables.

1. Identifying Output of an AND Gate

   Given an AND gate with two inputs A and B, what will be the output if A is 1 and B is 0?

   1. 0
   2. 10
   3. 1
   4. A

   Explanation: An AND gate outputs 1 only if both inputs are 1; otherwise, it outputs 0. Here, since A is 1 and B is 0, the output will be 0. The option '1' is incorrect because both inputs are not high. '10' is not valid output in this context, and 'A' merely repeats one input rather than showing the logical result of the operation.

2. Selecting the Correct Truth Table for a NAND Gate

   Which of the following represents the output for a two-input NAND gate when both inputs A and B are 1?

   1. 1
   2. 0
   3. 2
   4. -1

   Explanation: A NAND gate outputs 0 only when both inputs are 1; otherwise, its output is 1. The answer is 0, matching this rule. Option '1' is incorrect, as that would be true for an AND gate. '2' is not a possible output for logic gates, and '-1' is not a valid binary value.

3. Finding the Gate for Inverting Input

   Which logic gate produces an output opposite to its single input, for example, outputting 1 when input is 0?

   1. OR
   2. NOT
   3. NOR
   4. NAND

   Explanation: The NOT gate, also known as an inverter, outputs the logical opposite of its input. If the input is 0, the output is 1 and vice versa. 'NOR' and 'NAND' are multi-input gates with different logic. 'OR' outputs 1 if at least one input is 1 but does not invert the input.

4. Interpreting an OR Gate’s Output

   If the inputs to a two-input OR gate are A = 0 and B = 1, what will the output be?

   1. A
   2. 0
   3. 1
   4. B

   Explanation: An OR gate outputs 1 if at least one of its inputs is 1. Since B is 1, the output is 1. '0' would only be correct if both inputs were 0. The answers 'A' and 'B' simply repeat the input values and do not represent the logical operation’s output.

5. Determining Unique Property of XOR Gate

   Which is true about the output of a two-input XOR (exclusive OR) gate when both its inputs are the same, such as A = 1 and B = 1?

   1. Output is 0
   2. Output equals A
   3. Output alternates
   4. Output is 1

   Explanation: An XOR gate outputs 1 only when its inputs differ; when both inputs are the same (either both 0 or both 1), the output is 0. 'Output is 1' would be correct if the inputs were different. 'Output equals A' is misleading since the XOR calculates based on both inputs, and 'Output alternates' is not specific to XOR gate logic.