The first operation involved in a Carnot cycle is

Options

A. Isothermal expansion
B. Adiabatic expansion
C. Isothermal compression
D. Adiabatic compression

Answer

To solve the question regarding the first operation involved in a Carnot cycle, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Carnot Cycle**:
The Carnot cycle consists of four distinct processes: two isothermal processes and two adiabatic processes. The cycle is represented on a Pressure-Volume (PV) diagram.

2. **Identifying the Processes**:
The four processes in a Carnot cycle are:
- Process 1-2: Isothermal Expansion
- Process 2-3: Adiabatic Expansion
- Process 3-4: Isothermal Compression
- Process 4-1: Adiabatic Compression

3. **Analyzing the First Process**:
In the PV diagram, the first operation (from point 1 to point 2) is the isothermal expansion. During this process, the gas expands at a constant temperature, absorbing heat from the hot reservoir.

4. **Conclusion**:
Since the first operation in the Carnot cycle is the isothermal expansion, the correct answer to the question is:
- **Isothermal Expansion**.

### Final Answer:
The first operation involved in a Carnot cycle is **Isothermal Expansion**.

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