Assertion : Lines of force are perpendicular to conductor surface.
Reason : Generally electric field is perpendicular to equipotential surface.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

To solve the question, we need to analyze the assertion and the reason provided.

### Step 1: Understanding the Assertion
The assertion states that "Lines of force are perpendicular to the conductor surface." This is a fundamental property of electrostatics. When a conductor is in electrostatic equilibrium, the electric field inside the conductor is zero. As a result, the electric field lines (or lines of force) must be perpendicular to the surface of the conductor. If they were not perpendicular, there would be a component of the electric field parallel to the surface, which would cause charges to move, contradicting the condition of electrostatic equilibrium.

### Step 2: Understanding the Reason
The reason states that "Generally, electric field is perpendicular to equipotential surface." This is also true. An equipotential surface is one where the electric potential is constant. If the electric field were not perpendicular to the equipotential surface, there would be a potential difference along the surface, which would imply that work is done when moving a charge along the surface. This contradicts the definition of equipotential surfaces.

### Step 3: Connecting Assertion and Reason
Both the assertion and the reason are true statements. The assertion correctly describes the behavior of electric field lines at the surface of a conductor, while the reason correctly describes the relationship between electric fields and equipotential surfaces. Furthermore, the reason provides a valid explanation for the assertion because the perpendicularity of electric field lines to the conductor surface is a direct consequence of the electric field being perpendicular to equipotential surfaces.

### Conclusion
Both the assertion and the reason are true, and the reason is a correct explanation of the assertion.

### Final Answer
- Assertion: True
- Reason: True
- Explanation: The reason is a correct explanation for the assertion.

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