An unbalanced force is a force or combination of forces acting on an object where the total (net) force is not zero. This means the forces do not cancel each other out, resulting in a change in the object's motion—such as starting to move, speeding up, slowing down, or changing direction
. Key points about unbalanced forces:
- They occur when forces acting on an object are unequal in magnitude or not opposite in direction, producing a net force greater than zero
- Unbalanced forces cause acceleration, meaning the object’s velocity changes in speed, direction, or both
- They are necessary to change the state of motion of an object, for example, making a stationary object start moving or altering the motion of a moving object
- Examples include a tug-of-war where one team pulls harder than the other, kicking a soccer ball, or a car accelerating when the engine force overcomes friction
In contrast, balanced forces have equal magnitude and opposite directions, resulting in a net force of zero, so the object’s motion does not change
. In summary, an unbalanced force is any force or set of forces whose resultant is not zero, causing an object to accelerate or change its motion
