A : The work done by a force during round trip is always zero.
R : The average value of force in round trip is zero.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3).
D. If both Assertion and Reason are falsė statements, then mark (4).

Answer

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

### Step 1: Understand the Assertion (A)
The assertion states that "The work done by a force during a round trip is always zero."

- When a force acts on an object, the work done (W) is calculated using the formula:
\[ W = F \cdot s = F \cdot d \cdot \cos(\theta) \]
where \(F\) is the force, \(s\) is the displacement, and \(\theta\) is the angle between the force and the displacement vector.

- In a round trip, the object returns to its original position. Therefore, the total displacement is zero.

- Since displacement is zero, the work done during the round trip can be expressed as:
\[ W = F \cdot 0 = 0 \]

Thus, the assertion (A) is **true**.

### Step 2: Understand the Reason (R)
The reason states that "The average value of force in a round trip is zero."

- The average force is defined as the total force applied divided by the total time or the total displacement over the time taken.

- In a round trip, while the net displacement is zero, the forces applied during the trip may not necessarily average out to zero. For example, if a constant force is applied in one direction, the average force will still be that constant value, even if the object returns to the starting point.

- Therefore, the average value of force can be non-zero, depending on the nature of the forces applied during the trip.

Thus, the reason (R) is **false**.

### Conclusion
- The assertion (A) is true.
- The reason (R) is false.

### Final Answer
The correct option is: Assertion is true, Reason is false.

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