Each diode in figure can be described by a cut-in voltage

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Each diode in figure can be described by a cut-in voltage and zero resistance. If the cut-in voltage of diode D1 is 0·2V and of diode D2 is 0·6 V, the magnitude of current i₁ through D1 is ………… mA and magnitude of current through D2 is ………… mA.

1. 20 mA, 0 mA
2. 10 mA, 0 mA
3. 15 mA, 0 mA
4. 25 mA, 0 mA

Correct Option: B

The given circuit (i.e., fig- 1)
Given that cut-in voltage of diode D₁ is 0·2V and D₂ is 0·6V. Since the cut-in voltage of diode D₁ is 0·2V i.e., less than the cut-in voltage of diode D₂ is 0·6V, which prevents the diode D₂ turning ‘ON’. There fore the equivalent circuit is given by (i.e., fig- 2)

Now, I₁ =		(100 – 0·2)V	=	99·8V
		10 KΩ		10 KΩ

= 9·98 mA 10 mA
and I₂ = 0 mA
Hence alternative (B) is the correct choice.