Modern Physics Ques 238
- The truth table for the circuit given in the figure is
(Main 2019, 12 April I)
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Answer:
Correct Answer: 238.(c)
Solution:
Formula:
- Given circuit is
Let the intermediate state $X$ of OR gate is shown in figure.
Clearly, $Y=\overline{A X}$
Here, $X=A+B$
$\therefore \quad Y=\overline{A(A+B)}=\overline{A A+A B}$
$ \begin{aligned} & = \quad \overline{A+A B} \\ & = \quad \overline{A(1+B)} \end{aligned} $
$\Rightarrow \quad Y=\bar{A}$ $\quad (\because 1+B=1)$
So, truth table shown in option (c) is correct.
Alternate Solution
We can solve it using truth table
| $\boldsymbol{A}$ | $\boldsymbol{B}$ | $\boldsymbol{X}=\boldsymbol{A}+\boldsymbol{B}$ | $\boldsymbol{Y}=\overline{\boldsymbol{A} \boldsymbol{X}}$ |
|---|---|---|---|
| 0 | 0 | 0 | 1 |
| 0 | 1 | 1 | 1 |
| 1 | 0 | 1 | 0 |
| 1 | 1 | 1 | 0 |
BETA
