The first law of theromodynamics is a statement of

Options

A. conservation of heat
B. conservation of work
C. conservation of momentum
D. conservation of energy

Explanation

To solve the question regarding the first law of thermodynamics, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the First Law of Thermodynamics**: The first law of thermodynamics is a fundamental principle that relates to energy conservation in thermodynamic processes. It states that energy cannot be created or destroyed, only transformed from one form to another.

2. **Identify the Components**: In the context of the first law, we have:
- \( Q \): the amount of heat added to the system.
- \( W \): the work done by the system.
- \( \Delta U \): the change in internal energy of the system.

3. **Formulate the First Law**: The first law can be mathematically expressed as:
\[ Q = \Delta U + W \]
This equation indicates that the heat added to the system is equal to the change in internal energy plus the work done by the system.

4. **Interpret the Equation**: This equation shows that the total energy input (heat) into the system is equal to the energy output (work done) plus the change in the system's internal energy. This is a clear representation of the conservation of energy principle.

5. **Conclusion**: Therefore, the first law of thermodynamics is a statement of the conservation of energy.

### Final Answer:
The first law of thermodynamics is a statement of conservation of energy.

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