Molecular motion shows itself as

Options

A. temperature
B. internal energy
C. friction
D. viscosity

Answer

To solve the question "Molecular motion shows itself as", we need to analyze the options provided: temperature, internal energy, friction, and viscosity.

### Step-by-Step Solution:

1. **Understanding Molecular Motion**:
- Molecular motion refers to the movement of molecules in a substance. This motion can be observed in gases, liquids, and solids, but it is most pronounced in gases.

2. **Identifying the Options**:
- The options given are:
- Temperature
- Internal Energy
- Friction
- Viscosity

3. **Analyzing Each Option**:
- **Temperature**:
- Temperature is a measure of the average kinetic energy of the molecules in a substance. It reflects how fast the molecules are moving. Higher temperatures correspond to higher molecular motion.
- **Internal Energy**:
- Internal energy includes both kinetic and potential energy of the molecules. While kinetic energy is related to molecular motion, potential energy may not be directly linked to motion.
- **Friction**:
- Friction is a force that opposes motion between surfaces. It does not directly relate to molecular motion itself.
- **Viscosity**:
- Viscosity is a measure of a fluid's resistance to flow and is influenced by molecular motion, but it is not a direct representation of that motion.

4. **Conclusion**:
- The most direct representation of molecular motion is temperature, as it is fundamentally linked to the kinetic energy of the molecules. Therefore, the answer is **temperature**.

### Final Answer:
Molecular motion shows itself as **temperature**.

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