Assertion : An ac generator is based on the self inductance of the coil.
Reason : Self inductance involves two coils.

Explanation

To analyze the given assertion and reason, we will break down the concepts involved and evaluate their correctness step by step.

### Step 1: Understanding the Assertion
**Assertion**: An AC generator is based on the self-inductance of the coil.

- An AC generator, also known as an alternator, converts mechanical energy into electrical energy through electromagnetic induction. It primarily operates on the principle of Faraday's law of electromagnetic induction, which states that a change in magnetic flux through a coil induces an electromotive force (emf) in that coil.
- Self-inductance refers to the property of a coil where a change in current through the coil induces an emf in the same coil due to its own magnetic field.

**Conclusion**: The assertion is incorrect because an AC generator operates based on Faraday's law, not solely on self-inductance.

### Step 2: Understanding the Reason
**Reason**: Self-inductance involves two coils.

- Self-inductance is defined for a single coil. It is the phenomenon where a change in current in a coil induces an emf in the same coil due to its own changing magnetic field.
- In contrast, mutual inductance involves two coils, where a change in current in one coil induces an emf in another coil.

**Conclusion**: The reason is also incorrect because self-inductance pertains to a single coil, not two.

### Final Evaluation
- Since both the assertion and the reason are false, the correct answer is that both the assertion and the reason are incorrect.

### Final Answer
Both the assertion and the reason are false.

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