(A) : A reference frame attached to earth is a non inertial frame of reference.
(R) : The reference frame which has an acceleration is called a non inertial frame of reference.

Options

A. Both (A) and (R) are true and (R) is the correct explanation of (A)
B. Both (A) and (R) are true and (R) is not the
C. (A) is true but ( R) is false
D. Both (A) and (R ) are false

Answer

To solve the problem, we need to analyze the assertion (A) and the reason (R) provided in the question.

### Step 1: Understanding the Assertion
The assertion states: "A reference frame attached to Earth is a non-inertial frame of reference."

- A reference frame is considered non-inertial if it is accelerating or if it is rotating. Since the Earth is rotating about its own axis and also revolving around the Sun, it is indeed undergoing acceleration. Therefore, the assertion is **true**.

### Step 2: Understanding the Reason
The reason states: "The reference frame which has an acceleration is called a non-inertial frame of reference."

- This statement is also true. By definition, a non-inertial frame of reference is one that is accelerating. If a frame of reference is accelerating, it does not adhere to Newton's first law of motion (the law of inertia), which states that an object at rest will remain at rest and an object in motion will remain in motion unless acted upon by a net external force.

### Step 3: Establishing the Relationship Between A and R
Now we need to determine if the reason (R) correctly explains the assertion (A).

- Since the Earth is indeed accelerating (due to its rotation and revolution), and this leads us to conclude that the frame attached to Earth is non-inertial, we can say that the reason provides a valid explanation for the assertion.

### Conclusion
Both the assertion (A) and the reason (R) are true, and R is the correct explanation of A.

Thus, the correct answer is: **Both A and R are true, and R is the correct explanation of A.**

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