AI Tutor
Imagine you and your friend push against opposite sides of a giant box with the exact same strength. The box does not budge at all because your pushes cancel each other out!
What rules determine whether an object stays totally still, speeds up, slows down, or swerves into a turn?

When Forces Balance Out

A force is simply a push or a pull, measured in standard units called newtons (N). When all forces acting on an object are equal in size and point in opposite directions, they are balanced forces.
The net force is the total leftover force after you combine all pushes and pulls on an object. In 1687, English scientist Isaac Newton showed that when the net force is zero, an object's motion does not change at all.
But what happens the moment one force becomes stronger than the other?

When Forces Are Unbalanced

When opposing forces are unequal, they are unbalanced forces, leaving a net force greater than zero. This leftover force always causes an object to change its speed or direction.
Because the push to the left is 10 N stronger, the wagon accelerates in the direction of that winning force.
How can you look at any force diagram and instantly predict what will happen next?

Predicting Motion Changes