Newton assumed that sound propagation in a gas takes under

Options

A. isothemal condition
B. adiabatic condition
C. isobaric condition
D. isentropic condition

Explanation

To solve the question regarding Newton's assumption about sound propagation in a gas, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Sound Propagation**: Sound is a mechanical wave that travels through a medium (like a gas) by causing the particles of the medium to vibrate. The nature of this propagation can be influenced by various thermodynamic conditions of the gas.

2. **Identify the Conditions**: The question provides four conditions: isothermal, adiabatic, isobaric, and isotropic. We need to determine which condition Newton assumed for sound propagation in gases.

3. **Define the Conditions**:
- **Isothermal Condition**: This condition occurs when the temperature of the gas remains constant during the process.
- **Adiabatic Condition**: In this condition, no heat is exchanged with the surroundings, leading to changes in temperature.
- **Isobaric Condition**: This condition occurs at constant pressure.
- **Isotropic Condition**: This refers to properties being the same in all directions.

4. **Newton's Assumption**: Newton assumed that during the propagation of sound in a gas, the temperature of the gas remains constant. This leads us to conclude that the sound propagation occurs under isothermal conditions.

5. **Conclusion**: Therefore, the correct answer to the question is that Newton assumed sound propagation in a gas takes place under **isothermal conditions**.

### Final Answer:
Newton assumed that sound propagation in a gas takes place under **isothermal conditions**.

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