Here's why:
* Newton's First Law of Motion states that an object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
* Balanced forces are equal in magnitude and opposite in direction. This means they cancel each other out.
* Unbalanced forces, on the other hand, have a net force that results in a change in motion (acceleration).
Examples of balanced forces:
* A book sitting on a table: The force of gravity pulling the book down is balanced by the normal force of the table pushing the book up.
* A person standing still: The force of gravity pulling the person down is balanced by the normal force of the ground pushing the person up.
* A car driving at a constant speed: The force of the engine pushing the car forward is balanced by the force of friction and air resistance acting against it.
Key takeaway: If the net force acting on an object is zero (i.e., the forces are balanced), the object's motion will not change.
