Assuming forward bias condition (voltage drop 0.7 V per silicon diode), find current through diode D1 in the given circuit. All diodes identical.

Options: A) 20.15 mA B) 11.7 mA C) 17.6 mA D) 18.8 mA

Solution

Apply Kirchhoff's loop rule. Net effective voltage after diode drop: 12 − 0.7 = 11.3 V Using symmetry and branch current division: Total current I ≈ 37.6 mA Current through D1: I₁ = I / 2 I₁ ≈ 18.8 mA Correct Answer: D

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IAT 2025 Question Paper

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