In which of the following media can sound travel through?
(i) Glass of water (ii) Balloon full of air
(iii) Iron bar (iv) Vacuum

Options

A. (i) and (ii) only
B. (ii) and (iii) only
C. (i), (ii) and (iii) only
D. (i), (ii), (iii) and (iv)

Answer

To determine in which of the given media sound can travel, we need to analyze each option based on the properties of sound and the nature of the media.

### Step-by-Step Solution:

1. **Understanding Sound Propagation**:
- Sound is a mechanical wave that requires a medium (solid, liquid, or gas) to travel. It cannot travel through a vacuum because there are no particles to transmit the sound waves.

2. **Analyzing Each Option**:
- **(i) Glass of Water**:
- Water is a liquid, and sound can travel through liquids. Therefore, sound can travel through a glass of water.

- **(ii) Balloon Full of Air**:
- Air is a gas, and sound can travel through gases. Hence, sound can travel through a balloon full of air.

- **(iii) Iron Bar**:
- Iron is a solid, and sound travels fastest in solids due to closely packed particles. Therefore, sound can travel through an iron bar.

- **(iv) Vacuum**:
- A vacuum is the absence of matter, meaning there are no particles to carry sound waves. Thus, sound cannot travel through a vacuum.

3. **Conclusion**:
- Sound can travel through the following media:
- (i) Glass of water
- (ii) Balloon full of air
- (iii) Iron bar
- Sound cannot travel through:
- (iv) Vacuum

### Final Answer:
Sound can travel through (i) Glass of water, (ii) Balloon full of air, and (iii) Iron bar. Sound cannot travel through (iv) Vacuum.

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