Assertion : In a freely falling liquid container, upthrust force is zero.
Reason : In freely falling case value of effective value of g is zero.

Options

A. (a)If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
B. (b)If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
C. (C)If Assertion is true but Reason is false.
D. (d)If Assertion is false but Reason is true.

Explanation

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

### Step-by-Step Solution:

**Step 1: Understand the Assertion**
- The assertion states that "In a freely falling liquid container, upthrust force is zero."
- Upthrust (or buoyant force) is the force exerted by a fluid that opposes the weight of an object submerged in it.

**Step 2: Analyze the Condition of Free Fall**
- In a freely falling container, both the container and the liquid inside it are accelerating downwards due to gravity.
- This means that everything inside the container, including the liquid, experiences the same acceleration (g).

**Step 3: Evaluate the Upthrust Force**
- The upthrust force is given by the formula:
\[ \text{Upthrust} = V \cdot \rho \cdot g \]
where \( V \) is the volume of the displaced fluid, \( \rho \) is the density of the fluid, and \( g \) is the acceleration due to gravity.
- In a freely falling container, while \( V \) and \( \rho \) are not zero, the effective value of \( g \) is effectively zero because the container and the liquid are in free fall together.

**Step 4: Understand the Reason**
- The reason states that "In freely falling case, the effective value of g is zero."
- This is true because, in free fall, the gravitational force does not create any net force acting on the liquid in the container, making it feel weightless.

**Step 5: Conclusion**
- Since both the assertion and the reason are correct, and the reason correctly explains the assertion, we conclude that:
- Both the assertion and reason are correct, and the reason is the correct explanation of the assertion.

### Final Answer:
Both the assertion and reason are correct, and the reason is the correct explanation of the assertion.

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