(A) : Newton's third law of motion is applicable only when bodies are in motion.
(R) : Newton's third law is not applicable to all types of forces. Like gravitational, electric or magnetic forces etc.

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 correct explanation of A
C. (A) is true but ( R) is false
D. Both (A) and (R ) are false

Answer

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

### Step 1: Understand the Assertion
The assertion states: "Newton's third law of motion is applicable only when bodies are in motion."

**Analysis**:
Newton's third law of motion states that for every action, there is an equal and opposite reaction. This law applies not only when bodies are in motion but also when they are at rest. For example, when you sit on a chair, your body exerts a downward force on the chair (action), and the chair exerts an equal and opposite force upward (reaction). Therefore, the assertion is **false**.

### Step 2: Understand the Reason
The reason states: "Newton's third law is not applicable to all types of forces, like gravitational, electric, or magnetic forces, etc."

**Analysis**:
Newton's third law is indeed applicable to all types of forces, including gravitational, electric, and magnetic forces. For instance, the gravitational force between two masses is an action-reaction pair. Thus, the reason provided is also **false**.

### Step 3: Conclusion
Since both the assertion and the reason are false, we conclude that the correct answer is that both A and R are false.

### Final Answer:
Both A and R are false.

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