Universe is an example of

Options

A. Open system
B. Close system
C. Isolated system
D. Closed isothermal system

Answer

To determine what the universe is an example of, we need to analyze the definitions of the different types of thermodynamic systems provided in the question. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Types of Thermodynamic Systems
1. **Open System**: In an open system, both energy and matter can be exchanged with the surroundings.
2. **Closed System**: In a closed system, only energy can be exchanged with the surroundings, while matter cannot be exchanged.
3. **Isolated System**: In an isolated system, neither energy nor matter can be exchanged with the surroundings.
4. **Closed Isothermal System**: This is a specific type of closed system where the temperature remains constant (ΔT = 0).

### Step 2: Analyze the Universe
- The universe encompasses all matter and energy. It is a vast system that contains everything.
- The total mass of the universe is considered to be constant, meaning that while energy can transform from one form to another, the amount of matter does not change.

### Step 3: Determine the Correct Classification
- Since the universe allows for the transformation of energy but does not allow for the exchange of matter with any surroundings (as it is all-encompassing), it fits the definition of a closed system.
- Therefore, the universe is not an open system (as it does not exchange matter), nor is it an isolated system (as energy transformations do occur). It is also not a closed isothermal system, as temperature changes can occur.

### Conclusion
Based on the analysis, the universe is best classified as a **closed system**.

### Final Answer
The universe is an example of a **closed system**.

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