The apparent weight of wood floating on water if it weights `100` g in air is

Options

A. `400` g
B. `300` g
C. `100` g
D. zero

Explanation

To solve the problem of finding the apparent weight of wood floating on water when its weight is 100 g in air, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Apparent Weight**:
- The apparent weight of an object submerged or floating in a fluid is affected by the buoyant force acting on it. The buoyant force is equal to the weight of the fluid displaced by the object.

2. **Identify the Given Information**:
- The weight of the wood in air (Fw) = 100 g.

3. **Apply the Principle of Buoyancy**:
- For an object floating in a fluid, the buoyant force (Fb) is equal to the weight of the object (Fw). Therefore, we can write:
\[ Fw = Fb \]
- This means that the weight of the wood (100 g) is balanced by the buoyant force.

4. **Calculate the Apparent Weight**:
- The apparent weight (Wa) can be calculated using the formula:
\[ Wa = Fw - Fb \]
- Since Fw = Fb for a floating object, we substitute:
\[ Wa = Fw - Fw = 0 \]

5. **Conclusion**:
- The apparent weight of the wood floating on water is 0 g.

### Final Answer:
The apparent weight of the wood floating on water is **0 g**.

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