question_answer 22)

  In Fig. 9(EP).2, assuming the diodes to be ideal (a) D1 is forward biased and D2 is reverse biased and hence current flows from A to B (b) D2 is forward biased and D1 is reverse bisaded and hence no current flows from B to A and vice versa                    (c) D1 and D2 are both forward biased and hence current flows from A to B (d) D1 and D2 are both reverse biased and hence no current flows from A to B and vice versa                 (a) 220V                               (b) 110V                 (c) 0V                                    (d)

Answer:

                                                 (b) In the given circuit, p-side of p-n junction D1 is connected to lower voltage and n-side of D1 to higher voltage. Therefore, D1 is reverse biased. 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, current flows through the junction from B to A, i.e., option (b) is correct.