Q 12-14-146JEE MainJEE Main 2021 (20 Jul, Shift 2)Easy
For the forward biased diode characteristics shown in the figure, the dynamic resistance at $I_D = 3$ mA will be ______ $\Omega$.
Numerical value type. Enter your answer.
Answer: 25
Around $I_D = 3$ mA the curve passes through (0.65 V, 1 mA) and (0.75 V, 5 mA):
$$r_d = \frac{\Delta V}{\Delta I} = \frac{0.75 - 0.65}{(5 - 1)\times10^{-3}} = \frac{0.1}{4\times10^{-3}} = 25\ \Omega$$
Solution by Sreeraj P, M.Sc Physics