Assertion (A): Ideal diode shows zero resistance in forward bias and infinite resitance in reverse bias.
Reason (R): Depletion region of a p-n junction diode extends in reverse bias and contracts in forward bias.

Options

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is NOT the correct explanation of A
C. A is true but R is false
D. A is false and R is true

Explanation

To solve the question regarding the assertion and reason about the ideal diode and the behavior of the depletion region in a p-n junction diode, we can follow these steps:

### Step 1: Understand the Assertion
The assertion states that an ideal diode shows zero resistance in forward bias and infinite resistance in reverse bias.

- **Forward Bias**: When a diode is forward-biased, the p-side is connected to a higher potential than the n-side. This allows current to flow easily through the diode, resulting in zero resistance.

- **Reverse Bias**: When a diode is reverse-biased, the n-side is connected to a higher potential than the p-side. This prevents current from flowing, leading to infinite resistance.

### Step 2: Understand the Reason
The reason provided states that the depletion region of a p-n junction diode extends in reverse bias and contracts in forward bias.

- **Depletion Region in Forward Bias**: When the diode is forward-biased, the applied voltage reduces the width of the depletion region. This reduction allows majority charge carriers (holes in p-type and electrons in n-type) to recombine more easily, increasing conductivity and decreasing resistance.

- **Depletion Region in Reverse Bias**: In reverse bias, the applied voltage increases the width of the depletion region. This expansion makes it harder for majority carriers to cross the junction, leading to decreased conductivity and increased resistance.

### Step 3: Analyze the Relationship
Now, we need to analyze the relationship between the assertion and the reason:

- The assertion is true because an ideal diode indeed has zero resistance in forward bias and infinite resistance in reverse bias.

- The reason is also true because it accurately describes the behavior of the depletion region in both forward and reverse bias conditions.

### Step 4: Conclusion
Since both the assertion and the reason are true, and the reason correctly explains the assertion, we conclude that:

- **Both Assertion (A) and Reason (R) are true, and R is the correct explanation of A.**

### Final Answer
Both Assertion (A) and Reason (R) are true, and R is the correct explanation of A.

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