Q.
The $VI$ characteristic of a diode is shown in the figure. The ratio of forward to reverse bias resistance is,

NTA AbhyasNTA Abhyas 2022
Solution:
The $VI$ characteristic of a diode is represented in the figure.
We can see that for forward bias, it offers much less resistance while in reverse bias, the resistance offered is much larger than in the forward bias.
Forward bias resistance $=\frac{\Delta V}{\Delta I}=\frac{0.1}{10 \times 10^{- 3}}=10 \, \Omega$ .
Reverse bias resistance $=\frac{10}{10^{- 6}}=10^{7}\Omega$ .
Ratio of resistances $=\frac{Forward bias resistance}{Reverse bias resistance}=10^{- 6}$ .
We can see that for forward bias, it offers much less resistance while in reverse bias, the resistance offered is much larger than in the forward bias.
Forward bias resistance $=\frac{\Delta V}{\Delta I}=\frac{0.1}{10 \times 10^{- 3}}=10 \, \Omega$ .
Reverse bias resistance $=\frac{10}{10^{- 6}}=10^{7}\Omega$ .
Ratio of resistances $=\frac{Forward bias resistance}{Reverse bias resistance}=10^{- 6}$ .