Question

Assuming the diode in the given circuit diagram to be a silicon p-n junction diode, what is the current for the given circuit diagram?

(a) 0

(b) 5 mA

(c) 4.3 mA

(d) Can’t be determined

I had been asked this question in a national level competition.

Enquiry is from Diode Basics and Equivalent Circuits in division Diode Circuit of Analog Circuits

Answer 1

The correct answer is (c) 4.3 mA

Best explanation: 4.3 mA. The silicon diode in the circuit is forward biased. Considering a voltage drop of 0.7 V across the diode, the voltage drop across the resistor is (5-0.7) V = 4.3 V. Hence, Current in the circuit = Current through the resistor = (4.3/1000) A = 4.3 mA.