Through which of these four boxes would sound not be able to travel ?

Options

A. A box filled with air
B. A box filled with wood
C. A box filled with water
D. A box with vacuum

Answer

To determine through which of the four boxes sound would not be able to travel, we need to analyze the properties of each medium present in the boxes.

### Step-by-Step Solution:

1. **Identify the Boxes**: We have four boxes:
- Box A: Filled with air
- Box B: Filled with wood
- Box C: Filled with water
- Box D: Filled with vacuum

2. **Understanding Sound Propagation**: Sound is a mechanical wave that requires a medium to travel. The three types of media are:
- Solids
- Liquids
- Gases

3. **Analyze Each Box**:
- **Box A (Air)**: Air is a gas and contains particles. Sound can travel through air as it allows the vibrations of molecules to propagate.
- **Box B (Wood)**: Wood is a solid. Sound can travel through solids as well, due to the close proximity of particles that can transmit vibrations.
- **Box C (Water)**: Water is a liquid. Sound can travel through liquids, as the molecules can also transmit vibrations.
- **Box D (Vacuum)**: A vacuum is an empty space with no particles or molecules. Since sound requires a medium (particles) to propagate, it cannot travel through a vacuum.

4. **Conclusion**: The box through which sound would not be able to travel is Box D, the one filled with vacuum.

### Final Answer:
**Sound cannot travel through Box D (Vacuum).**

---