Concept:In circuit analysis, an ideal diode under reverse bias provides infinite resistance and conducts zero current, modeling an open switch.
Formula:$$R_{\text{reverse}} = \infty, \quad I = 0\text{ A} \quad (\text{Ideal Diode Reverse Model})$$
Solution:- Under reverse bias, an ideal diode completely blocks current flow.
- It presents infinite reverse resistance (\( R_r = \infty \)).
- Therefore, it acts as an open circuit (open switch), dropping the full applied voltage across its terminals with zero current through the load.
Why other options are incorrect:- Option A: A short circuit with zero resistance models an ideal diode under forward bias.
- Option B: A constant \( 0.7\text{ V} \) drop models a conducting silicon diode under forward bias.
- Option D: A reverse-biased junction exhibits small depletion capacitance rather than inductive behavior.
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