A sound wave is sent into a gas pipe . Does its internal energy change ?

Answer

To determine whether the internal energy of a gas pipe changes when a sound wave is sent into it, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Internal Energy**:
- Internal energy is defined as the total energy contained within a system. It includes the kinetic and potential energies of the particles in the system.

2. **Identify the System**:
- In this case, the system is the gas inside the gas pipe. The gas particles possess internal energy due to their motion and interactions.

3. **Consider the Nature of Sound Waves**:
- Sound waves are mechanical waves that propagate through a medium (in this case, the gas) by causing the particles of the medium to vibrate.

4. **Energy Transfer**:
- When a sound wave travels through the gas, it transfers energy to the gas particles. This energy transfer causes the particles to vibrate more vigorously.

5. **Effect on Internal Energy**:
- As the sound wave imparts energy to the gas particles, the internal energy of the gas increases. This is because the internal energy is related to the motion of the particles, and increased motion (due to the energy from the sound wave) results in higher internal energy.

6. **Conclusion**:
- Therefore, when a sound wave is sent into a gas pipe, the internal energy of the gas does change, and specifically, it increases.

### Final Answer:
Yes, the internal energy of the gas in the pipe increases when a sound wave is sent into it.

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