Question

The current I through the circuit I if voltage v is -3V is? (Use constant voltage drop model of diode and take VD as 0.5V)

(a) 10mA

(b) 1mA

(c) 3mA

(d) 0mA

This question was addressed to me by my school principal while I was bunking the class.

I'm obligated to ask this question of Constant Voltage Drop Model-1 in chapter Diode Circuit of Analog Circuits

Answer 1

Right choice is (d) 0mA

The best I can explain: In constant voltage drop model, in forward bias, the diode can be replaced as a cell and a short circuit, and in reverse bias as an open circuit. In above circuit, the diode is reverse biased, hence when open circuited, no current flows.