question_answer

The circuit given below represents which of the logic operations?  

A) AND                            

B) NOT

C) OR                   

D) NOR

Correct Answer: A

Solution :

Let two inputs are A and B. The circuit can be shows as The two gates shown are NAND gates.      The output of gate \[- 1, {{Y}_{1}}, =\overline{A \cdot  B}\] The output of gate \[- 2, Y, =\overline{{{Y}_{1}} \cdot  {{Y}_{1}}}\] \[\operatorname{or} \,\,\,\,Y=\,\,\overline{\overline{A\,\cdot \,\,B} \cdot \overline{A\,\cdot \,\,B}}\] \[=\,\,\,\,\overline{\overline{A\,\cdot \,\,B}}\] \[=\,\,\,A\,\cdot \,\,B\] Thus, the combination behaves as it is an AND gate.