What does Newton's First Law of Motion establish about objects at rest and in motion?

Newton's First Law of Motion, often referred to as the Law of Inertia, states that an object will remain at rest or continue to move at a constant velocity in a straight line unless acted upon by an unbalanced external force. This principle highlights the concept of inertia, which is the tendency of an object to resist changes in its state of motion.

When this law is applied, it indicates that a stationary object will not start moving unless a force is applied to it. Conversely, an object in motion will not change its velocity or direction unless a force disrupts that state. This means that for both resting and moving objects, the presence of an opposing or unbalanced force is essential for changing their state of motion. This principle is fundamental in understanding how forces interact with objects and is a cornerstone in the field of mechanics.