For using a multimeter to identify diode from electrical components, choose the correct statement out of the following about the diode

We need to identify the correct statement about a diode when using a multimeter.

Understanding a Diode:

A diode is a semiconductor device with two terminals — the anode and the cathode.

Key Property of a Diode:

A diode conducts current in only one direction (forward bias). In reverse bias, it blocks current (except for a negligible leakage current).

Using a Multimeter to Identify a Diode:

When we use a multimeter in diode-test mode:

- In one orientation (forward bias): the multimeter shows a low resistance/voltage drop, indicating current flows.

- In the reverse orientation (reverse bias): the multimeter shows very high resistance (open circuit), indicating no current flows.

Evaluating the Options:

Option A: "Conducts current in both directions" — This describes a resistor, not a diode. Incorrect.

Option B: "Two terminal device which conducts current in one direction only" — This is the correct description of a diode.

Option C: "Does not conduct current, gives an initial deflection which decays to zero" — This describes a capacitor. Incorrect.

Option D: "Three terminal device" — A diode has only two terminals, not three. This describes a transistor. Incorrect.

Hence, the correct answer is Option B.