The term inertia was first used by

Options

A. 1.Newton
B. 2.Galileo
C. 3. Aristotle
D. 4. Kepler

Explanation

To solve the question "The term inertia was first used by," we need to identify the historical context and the contributions of the individuals mentioned in the options: Newton, Galileo, Aristotle, and Kepler.

### Step-by-Step Solution:

1. **Understanding the Term Inertia**:
- Inertia is the property of an object to resist changes in its state of motion. It is directly related to the mass of the object.

2. **Historical Background**:
- The concept of inertia has been discussed by various scientists throughout history, but the term itself has a specific origin.

3. **Identifying the Contributor**:
- **Galileo Galilei**: In the 17th century, Galileo was one of the first to describe the concept of inertia. He conducted experiments and laid the groundwork for understanding motion.
- **Isaac Newton**: Although Newton did not coin the term, he formulated the laws of motion, which include the law of inertia, in his work "Philosophiæ Naturalis Principia Mathematica" published in 1687.
- **Aristotle**: He had different views on motion and did not use the term inertia.
- **Johannes Kepler**: He is known for his laws of planetary motion but did not specifically address the concept of inertia.

4. **Conclusion**:
- Based on the historical contributions, the term "inertia" was first used by **Galileo**.

### Final Answer:
The term inertia was first used by **Galileo**.

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