A: magnetic field is produced by moving charges(s).
R: The magnetic field in the central region of a solenoid is uniform.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion then mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark 2.
C. If assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To solve the question regarding the assertion (A) and reason (R), we will analyze each statement step by step.

### Step 1: Analyze the Assertion (A)
**Assertion (A)**: "Magnetic field is produced by moving charges."

- **Explanation**: According to the principles of electromagnetism, specifically from Maxwell's equations, it is established that a magnetic field is generated by moving electric charges. When charges are in motion, they create a magnetic field around them. This is a fundamental concept in physics.

**Conclusion**: The assertion is **True**.

### Step 2: Analyze the Reason (R)
**Reason (R)**: "The magnetic field in the central region of a solenoid is uniform."

- **Explanation**: A solenoid is a coil of wire that produces a magnetic field when an electric current passes through it. Inside the solenoid, particularly in the central region, the magnetic field lines are parallel and evenly spaced, indicating that the magnetic field strength is constant and uniform. Outside the solenoid, the magnetic field is negligible.

**Conclusion**: The reason is also **True**.

### Step 3: Determine the Relationship Between A and R
Now that we have established that both statements are true, we need to determine if R is the correct explanation of A.

- **Analysis**: While both statements are true, the reason (R) does not explain why the assertion (A) is true. The assertion discusses the production of a magnetic field by moving charges, while the reason specifically pertains to the uniformity of the magnetic field in a solenoid, which is a separate phenomenon.

### Final Conclusion
Both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

### Answer:
The correct answer is: **Both A and R are true, but R is not the correct explanation of A.**

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