A : Gravitational force is the weakest force among all other forces.
R : Gravitational force between the two masses is independent of the medium in between.

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 analyze the given statements and determine their validity, we will follow these steps:

### Step 1: Evaluate Assertion (A)
- **Assertion (A)** states: "Gravitational force is the weakest force among all other forces."
- This statement is **correct**. Among the four fundamental forces (gravitational, electromagnetic, weak nuclear, and strong nuclear), the gravitational force is indeed the weakest.

### Step 2: Evaluate Reason (R)
- **Reason (R)** states: "Gravitational force between the two masses is independent of the medium in between."
- This statement is also **correct**. The gravitational force between two masses is given by the formula:
\[ F = \frac{G \cdot m_1 \cdot m_2}{r^2} \]
where \( G \) is the gravitational constant, \( m_1 \) and \( m_2 \) are the masses, and \( r \) is the distance between them. This formula shows that the gravitational force does not depend on the medium between the two masses.

### Step 3: Determine the Relationship Between A and R
- Now we need to check if Reason (R) can explain Assertion (A).
- The assertion states that gravitational force is the weakest force, while the reason states that it is independent of the medium. These two statements are independent of each other; the fact that gravitational force is weak does not relate to its independence from the medium.

### Conclusion
- Both statements are correct, but Reason (R) does not explain Assertion (A).
- Therefore, the correct option is: **Both statements are correct, but reason is not the correct explanation of assertion.**

### Final Answer
The correct option is **B**.

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