Here's why:
* Forces are pushes or pulls: When a force acts on an object, it tries to change the object's motion.
* Balanced forces cancel each other out: When forces are balanced, they act in opposite directions with equal strength. This means their effects on the object cancel each other out.
* No change in motion: Because the forces cancel each other out, there is no net force acting on the object. This means the object will either remain at rest (if it was already still) or continue moving at a constant speed and direction (if it was already moving).
Examples:
* A book resting on a table: Gravity pulls the book down, but the table pushes back up with an equal and opposite force. These forces are balanced, so the book stays at rest.
* A car moving at a constant speed: The engine provides a forward force, but friction from the road and air resistance act in the opposite direction. If these forces are balanced, the car will continue moving at a constant speed.
In short, balanced forces result in an object's motion staying the same – either at rest or moving at a constant speed and direction.
