A process that occurs without loss or gain of heat is

Options

A. coriolis effect
B. eustatic effectq
C. adiabatic
D. all the above

Answer

To solve the question, "A process that occurs without loss or gain of heat is," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question is asking for a specific type of process that does not involve any heat transfer.

2. **Analyze the Options**: The options given are:
- Coriolis effect
- Eustatic effect
- Adiabatic
- All of the above

3. **Define Each Term**:
- **Coriolis Effect**: This refers to the deflection of moving objects caused by the rotation of the Earth. It does not relate to heat transfer.
- **Eustatic Effect**: This involves changes in sea level due to alterations in the volume of water or the shape of ocean basins. This also does not pertain to heat transfer.
- **Adiabatic Process**: This is defined as a process in which no heat is transferred into or out of a system. The internal energy change is solely due to work done on or by the system.

4. **Identify the Correct Answer**: Since the question specifically asks for a process that occurs without loss or gain of heat, the correct answer is the **adiabatic process**.

5. **Conclusion**: Therefore, the process that occurs without loss or gain of heat is the **adiabatic process**.

### Final Answer:
The answer is **Adiabatic**.

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