Assertion: The centripetal forces and centrifugal forces never cancel out.
Reason: They do not act at the same time.

Options

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

Explanation

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

### Step 1: Understand the Assertion
The assertion states that "The centripetal forces and centrifugal forces never cancel out."

- **Centripetal Force**: This is the real force that acts on an object moving in a circular path, directed towards the center of the circle.
- **Centrifugal Force**: This is a perceived force that acts outward on a body moving in a circular path, felt in a rotating reference frame. It is considered a "pseudo" force because it arises from the inertia of the object in a non-inertial (rotating) frame of reference.

### Step 2: Analyze the Reason
The reason states that "They do not act at the same time."

- In a non-inertial frame (like a rotating frame), the centrifugal force is perceived by an observer who is rotating with the object. However, in an inertial frame, only the centripetal force is acting on the object.
- Since these forces are viewed from different frames of reference, they do not act simultaneously in the same frame.

### Step 3: Conclusion
Both the assertion and the reason are true:
- The assertion is true because centripetal and centrifugal forces cannot cancel each other out as they are not acting in the same frame of reference at the same time.
- The reason is also true because they do not act at the same time due to their dependence on the frame of reference.

### Final Answer
Both the assertion and the reason are true, and the reason correctly explains the assertion. Thus, the correct option is A.

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