How does Newton's First Law apply to objects at rest?

Newton's First Law states that an object at rest will stay at rest unless acted upon by a force.

Newton's First Law, also known as the law of inertia, tells us that objects do not change their state of motion unless a force is applied. For an object at rest, this means it will remain stationary until something causes it to move. This 'something' is an external force, which could be a push, a pull, or any other interaction that can cause a change in motion.

Imagine a book lying on a table. According to Newton's First Law, the book will stay there indefinitely unless a force acts on it. This force could be you picking it up, a gust of wind strong enough to move it, or even the table being tilted. Without such forces, the book remains at rest because there is no reason for it to start moving.

Inertia is the property of matter that resists changes in motion. For objects at rest, inertia means they will not start moving on their own. The more massive an object is, the greater its inertia, and the more force it will take to change its state of rest. For example, it is much easier to push a small toy car than a real car because the real car has much more mass and therefore much more inertia.

In summary, Newton's First Law explains why objects at rest stay at rest: they need an external force to overcome their inertia and set them in motion. This principle is fundamental in understanding how forces and motion work in the physical world.