Velocity of sound is minimum in:

Options

A. air
B. helium
C. hydrogen
D. oxygen

Explanation

To determine in which medium the velocity of sound is minimum, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Formula for Velocity of Sound**:
The velocity of sound (V) in a medium is given by the formula:
\[ V = \sqrt{\frac{\gamma P}{\rho}} \]
where:
- \( \gamma \) (gamma) is the specific heat ratio,
- \( P \) is the pressure,
- \( \rho \) (rho) is the density of the medium.

2. **Identify the Factors Affecting Sound Velocity**:
- The velocity of sound is influenced by the medium's density and pressure.
- Generally, sound travels faster in solids than in liquids, and faster in liquids than in gases.

3. **Compare the Velocities of Sound in Different Gases**:
- According to the video transcript, the velocities of sound in various gases are:
- Air: 2.33 m/s
- Oxygen: 3.30 m/s
- Helium: Approximately 12 m/s
- Hydrogen: More than helium
- From these values, we can see that air has the lowest velocity of sound compared to the other gases listed.

4. **Conclusion**:
Based on the comparison of sound velocities in different gases, we conclude that the velocity of sound is minimum in air.

### Final Answer:
The velocity of sound is minimum in **air**.

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