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Question
In the circuit shown in figure, if the diode forward voltage drop is 0.3 V, the voltage difference between A and B is ______.

Options
1.3 V
2.3 V
0
0.5 V
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Solution
In the circuit shown in figure, if the diode forward voltage drop is 0.3 V, the voltage difference between A and B is 2.3 V.
Explanation:
Let us consider figure 2.3 V given above in the problem, suppose the potential difference between A and B is VAB.
Then, `V_(AB) - 0.3 = [(r_1 + r_2)10^3] xx (0.2 xx 10^-3)` .....[∵ VAB = ir]
= `[(5 + 5)10^3] xx (0.2 xx 10^-3)]`
= `10 xx 10^3 xx 0.2 xx 10^-3`
= 2
⇒ VAB = 2 + 0.3 = 2.3 V
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