Which one of the following is not a derived unit?

Options

A. Joule
B. watt
C. Kilogram
D. newton

Explanation

To solve the question "Which one of the following is not a derived unit?" we need to understand the difference between fundamental units and derived units.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are:
- A) Joule
- B) Watt
- C) Kilogram
- D) Newton

2. **Define Fundamental and Derived Units**:
- **Fundamental Units**: These are the basic units that are not derived from other units. They represent fundamental quantities such as mass, length, time, electric current, temperature, amount of substance, and luminous intensity.
- **Derived Units**: These are units that are derived from fundamental units. They are formed by combining fundamental units.

3. **Analyze Each Option**:
- **Joule (A)**: This is a derived unit of energy. It is defined as one kilogram meter squared per second squared (kg·m²/s²).
- **Watt (B)**: This is a derived unit of power. It is defined as one joule per second (J/s), which can also be expressed as kg·m²/s³.
- **Kilogram (C)**: This is a fundamental unit of mass. It is not derived from any other unit.
- **Newton (D)**: This is a derived unit of force. It is defined as kg·m/s².

4. **Conclusion**: Among the options, the kilogram is the only unit that is not derived from any other unit. Therefore, the answer to the question is option C) Kilogram.

### Final Answer:
C) Kilogram

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