Two frame `S_(1)` and `S_(2)` are non-inertial. Then frame `S_(2)` when observed from `S_(1)` is inertial.
A frame in motion is not necessarily a non-inertial frame

Options

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

Explanation

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

### Step 1: Understanding the Assertion
The assertion states: "Two frames \( S_1 \) and \( S_2 \) are non-inertial."
- A non-inertial frame is one that is accelerating with respect to an inertial frame. Since both frames are stated to be non-inertial, this means they are both experiencing some form of acceleration.

### Step 2: Understanding the Reason
The reason states: "A frame in motion is not necessarily a non-inertial frame."
- This statement is true because a frame can be moving with a constant velocity, which means it is inertial. An inertial frame is one that is either at rest or moving at a constant velocity, thus not experiencing any acceleration.

### Step 3: Analyzing the Relationship Between Assertion and Reason
- The assertion claims that both frames are non-inertial, which is true. However, the reason explains that not all moving frames are non-inertial, which is also true but does not directly explain the assertion. Therefore, while both statements are true, the reason does not provide a correct explanation for the assertion.

### Step 4: Conclusion
Given the analysis:
- The assertion is true.
- The reason is true but does not explain the assertion.

Thus, the correct option is that the assertion is true but the reason is false.

### Final Answer
The assertion is true, but the reason is false.

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