In the given figure, a diode D is connected to an external resistance \( R = 100\,\Omega \) and an emf of 2.5 V. During forward bias, if the barrier potential developed across the diode is 0.6 V, the current in the circuit will be
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 19 mA
The diode and the resistor are in series with the cell. A forward-biased diode takes the barrier potential of 0.6 V across itself, and the rest of the emf drops across the resistor.
\( \displaystyle V_R = 2.5 - 0.6 = 1.9\,\mathrm{V} \)
\( \displaystyle I = \frac{V_R}{R} = \frac{1.9\,\mathrm{V}}{100\,\Omega} = 0.019\,\mathrm{A} = 19\,\mathrm{mA} \)