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Question
In Figure, assuming the diodes to be ideal ______.
Options
D1 is forward biased and D2 is reverse biased and hence current flows from A to B.
D2 is forward biased and D1 is reverse biased and hence no current flows from B to A and vice versa.
D1 and D2 are both forward biased and hence current flows from A to B.
D1 and D2 are both reverse biased and hence no current flows from A to B and vice versa.
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Solution
In Figure, assuming the diodes to be ideal D2 is forward biased and D1 is reverse biased and hence no current flows from B to A and vice versa.
Explanation:
A symbol of the diode is represented like this: In this problem first, we have to check the polarity of the diodes. –10 V is the lower voltage in the circuit. Now p-side of p-n Anode Cathode junction D1 is connected to lower voltage and n-side of D1 to the higher voltage. Thus D1 is reverse biased.
Now, let us analyse 2nd diode of the given circuit. The p-side of p-n junction D2 is at higher potential and n-side of D2 is at lower potential. Therefore D2 is forward biased.
Hence, the current flows through the junction from B to A.
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