Assertion Centripetel force `(mv^(2))//(R)` acts on a particle rotating in a circle.
Reason Summation of net force acting on the particle is equal to `(mv^(2))//(R)` in the above case.

Options

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

Explanation

To solve the question, we need to analyze the assertion and the reason separately and then determine their relationship.

### Step 1: Understand the Assertion
The assertion states that the centripetal force acting on a particle rotating in a circle is given by the formula:

\[ F_c = \frac{mv^2}{R} \]

where:
- \( F_c \) is the centripetal force,
- \( m \) is the mass of the particle,
- \( v \) is the tangential velocity of the particle,
- \( R \) is the radius of the circular path.

### Step 2: Understand the Reason
The reason states that the summation of the net force acting on the particle is equal to \( \frac{mv^2}{R} \). In circular motion, the net force acting on the particle must be directed towards the center of the circle to keep the particle moving in a circular path. This net force is indeed the centripetal force.

### Step 3: Analyze the Relationship
The assertion is correct because it correctly identifies the centripetal force acting on a particle in circular motion. The reason is also correct because it states that the net force acting on the particle is equal to the centripetal force, which is \( \frac{mv^2}{R} \). Therefore, the reason provides a valid explanation for the assertion.

### Conclusion
Both the assertion and the reason are correct, and the reason correctly explains the assertion. Thus, the answer to the question is that both the assertion and reason are true, and the reason is a correct explanation of the assertion.

### Final Answer
Option A is correct.

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