Assertion A charged particle is rotating in a circular path in uniform magnetic field. Then, plane of circle is perpendicular to the magnetic field.
Reason Circular motion is a two-dimensional motion.

Options

A. (a)If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B. (b)If both Assertion and Reason are true but Reason is not correct explanation of Assertion.
C. (c)If Assertion is true but Reason is false.
D. (d)If Assertion is false but Reason is true.

Answer

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

### Step 1: Understanding the Assertion
The assertion states that a charged particle is rotating in a circular path in a uniform magnetic field, and the plane of the circle is perpendicular to the magnetic field.

- In a uniform magnetic field, the magnetic force acts as a centripetal force on the charged particle, causing it to move in a circular path.
- For the magnetic force to act as the centripetal force, the velocity of the charged particle must be perpendicular to the magnetic field lines. This means that the plane of the circular motion must indeed be perpendicular to the direction of the magnetic field.

### Step 2: Understanding the Reason
The reason states that circular motion is a two-dimensional motion.

- Circular motion can be described in two dimensions (the plane of the circle). However, this fact alone does not explain why the plane of the circle is perpendicular to the magnetic field.
- The reason is true, but it does not provide a direct explanation for the assertion.

### Step 3: Conclusion
Both the assertion and the reason are true statements. However, the reason does not adequately explain the assertion. Therefore, the correct answer is that both statements are true, but the reason is not the explanation of the assertion.

### Final Answer
The correct option is B: Both assertion and reason are correct, but the reason is not the explanation of the assertion.

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