In which medium sound travel fastest

Options

A. solid
B. liquid
C. gas
D. vacuum

Explanation

To determine in which medium sound travels the fastest, we can analyze the properties of different states of matter: solids, liquids, gases, and vacuums.

### Step-by-Step Solution:

1. **Understanding Sound Waves**:
- Sound is a longitudinal wave that requires a medium to travel through. This means it cannot travel in a vacuum.

2. **Properties of Different Mediums**:
- **Solids**: In solids, molecules are closely packed together. This close proximity allows sound waves to transfer energy quickly from one molecule to another.
- **Liquids**: In liquids, molecules are less tightly packed than in solids, but they are still closer together than in gases. This allows sound to travel faster than in gases but slower than in solids.
- **Gases**: In gases, the molecules are much farther apart compared to solids and liquids. This increased distance means that sound waves take longer to transfer energy between molecules, resulting in slower sound travel.
- **Vacuum**: Sound cannot travel in a vacuum because there are no molecules to transmit the sound waves.

3. **Comparing Speeds**:
- Based on the arrangement of molecules in each medium, we can conclude that sound travels fastest in solids due to the close packing of molecules, which facilitates quicker energy transfer.

4. **Conclusion**:
- Therefore, the medium in which sound travels the fastest is **solid**.

### Final Answer:
Sound travels fastest in **solids**.