Assertion : In case of elastic collision between two objects , speed of approach is same as speed of separation .
Reason : In case of elastic collision between two objects , linear momentum of the system remains conserved .

Options

A. If both assertion and reason are corret and reason is a correct explanation of the assertion .
B. If both assertion and reason are correct but reason is ot the correct explanation of assertion .
C. If assertion is correct but reason is incorrect .
D. If both assertion and reason are incorrect .

Explanation

To solve the assertion and reason question regarding elastic collisions, we can break it down into a step-by-step analysis:

### Step 1: Understanding the Assertion
The assertion states that in the case of an elastic collision between two objects, the speed of approach is the same as the speed of separation.

**Explanation:**
- In an elastic collision, both momentum and kinetic energy are conserved.
- The coefficient of restitution (E) is defined as the ratio of the relative speed after the collision to the relative speed before the collision.
- For elastic collisions, E = 1, which implies that the speed of separation equals the speed of approach.

### Step 2: Understanding the Reason
The reason states that in the case of an elastic collision between two objects, the linear momentum of the system remains conserved.

**Explanation:**
- According to the law of conservation of momentum, if no external forces act on a system, the total momentum of the system before the collision is equal to the total momentum after the collision.
- In an isolated system (like two colliding balls with no external forces), the momentum is conserved.

### Step 3: Evaluating the Relationship Between Assertion and Reason
Now, we need to determine if the reason provided explains the assertion.

**Analysis:**
- Both the assertion and reason are correct statements.
- However, the reason does not directly explain why the speed of approach equals the speed of separation. The assertion is based on the definition of elastic collisions, while the reason is based on the conservation of momentum.

### Conclusion
Since both the assertion and reason are correct, but the reason does not explain the assertion, we conclude that the correct option is:

**Option 2: Both assertion and reason are correct, but reason is not the correct explanation of assertion.**

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