Inertia is the tendency of an object to resist changes in its state of motion. If an unbalanced force affects an object, several predictions can be made about possible changes in the straight line motion of the object:
1. The object will accelerate: If an unbalanced force acts on an object, the object will accelerate in the direction of the force. The greater the force, the greater the acceleration.
2. The object will change its velocity: If the force acting on the object is not in the same direction as its velocity, the object will change its velocity. The change in velocity will be in the direction of the force.
3. The object will change its direction: If the force acting on the object is perpendicular to its velocity, the object will change its direction. The object will move in a curved path.
4. The object will continue to move in a straight line: If the force acting on the object is balanced, the object will continue to move in a straight line at a constant velocity.
5. The object will stop moving: If the force acting on the object is greater than the force of friction, the object will eventually stop moving.