Assertion : The electric field due to a discrete charge configuration is not defined at the locations of the discrete charges.
Reason : For a surface charge distribution, electric field is discontinuous across the 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 given question, we will analyze both the assertion and the reason step by step.

### Step 1: Understand the Assertion
The assertion states that "the electric field due to a discrete charge configuration is not defined at the locations of the discrete charges."

- **Explanation**: The electric field \( E \) at a point in space due to a charge \( Q \) is given by the formula:
\[ E = \frac{kQ}{r^2} \]
where \( k \) is Coulomb's constant and \( r \) is the distance from the charge to the point where the field is being calculated. At the location of the charge itself (where \( r = 0 \)), this formula becomes undefined because it leads to division by zero. Therefore, the assertion is true.

### Step 2: Understand the Reason
The reason states that "for a surface charge distribution, the electric field is discontinuous across the surface."

- **Explanation**: When dealing with surface charge distributions, such as on a conductor, the electric field can change abruptly at the surface. Inside a conductor, the electric field is zero, while just outside the surface, it can have a non-zero value. This discontinuity in the electric field across the surface of the conductor is a well-known phenomenon in electrostatics. Thus, the reason is also true.

### Step 3: Determine the Relationship Between Assertion and Reason
Now we need to analyze whether the reason provided is a correct explanation of the assertion.

- **Analysis**: While both the assertion and the reason are true, the reason does not directly explain why the electric field is not defined at the locations of discrete charges. The assertion is based on the mathematical definition of the electric field at a point where a charge exists, while the reason discusses the behavior of the electric field across a surface charge distribution. Hence, the reason is not a correct explanation of the assertion.

### Conclusion
- The assertion is true.
- The reason is true but does not explain the assertion.
- Therefore, the correct answer is that the assertion is true, and the reason is true, but the reason is not a correct explanation of the assertion.

### Final Answer
The correct option is: Assertion is true, Reason is true, but Reason is not a correct explanation of Assertion.

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