* Inertia: Inertia is the property of matter that causes it to resist changes in its state of motion. This means an object at rest wants to stay at rest, and an object in motion wants to stay in motion at the same speed and direction.
* Newton's First Law: This law states that an object at rest will stay at rest, and an object in motion will stay in motion at a constant velocity unless acted upon by a net force.
The connection:
The first law directly describes inertia. It tells us that objects will not change their motion (either being at rest or moving at a constant velocity) unless acted upon by a force. This resistance to change is the very definition of inertia.
Examples:
* A book on a table: The book remains at rest because there is no net force acting on it. It exhibits inertia by resisting the change in its state of motion.
* A car moving at a constant speed: The car continues moving at the same speed and direction because the forces acting on it are balanced. It demonstrates inertia by resisting the change in its velocity.
In summary:
The first law of motion, also known as the law of inertia, is a fundamental principle that describes the inherent tendency of objects to resist changes in their state of motion. This resistance is what we call inertia.
