that an object will change its motion when acted on by an unbalanced force

This statement is a basic principle of physics, specifically Newton's First Law of Motion, also known as the Law of Inertia. Here's a step-by-step explanation:

1. An object at rest tends to stay at rest, and an object in motion tends to stay in motion, with the same direction and speed. This is the concept of inertia.

2. However, if an unbalanced force acts on the object, it will change its state of motion. An unbalanced force means that the forces acting on the object are not equal and opposite, so they don't cancel each other out.

3. The change in motion depends on the magnitude and direction of the unbalanced force. The object will accelerate in the direction of the unbalanced force.

4. For example, if you slide a book on a table, it eventually stops because of the unbalanced force of friction acting against the motion of the book. If you kick a ball, it changes its motion and moves in the direction you kicked it because of the unbalanced force from your foot.

5. Therefore, an object will change its motion when acted on by an unbalanced force. This is a fundamental concept in understanding how objects move and interact in the universe.