**Unbalanced Forces **cause an object to **accelerate **(change speed and/or direction).

The three diagrams represent balanced forces and unbalanced forces acting on the ends of a wishbone. These are forces applied by the hands of the two contestants in the Wishbone Breaking Contest.

**Diagram 1: **Balanced Forces expressed by the equation: A + B

When the two forces are equal and in opposite directions, the net sum of the two forces is ZERO.This means the wishbone doesn’t move. This is the desired result.

**Diagram 2: **Unbalanced Forces expressed by the equations: A < B; B > A

This diagram show that the wishbone has moved to the right, in the direction of Force B. Unbalanced Forces are needed to cause a stationary object to move. The object moves (accelerates) in the direction of the larger force, which is the pulling force of hand B.

**Diagram 3. **Unbalanced Forces expressed by the equations: A > B; B < A

This diagram show that the wishbone has moved to the left, in the direction of Force A. Unbalanced Forces are needed to cause a stationary object to move. The object moves (accelerates) in the direction of the larger force, which is the pulling force of hand A.

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