Unbalanced forces have what in a force diagram?

• A. Equal Length Arrows
• B. Balanced Forces
• C. Forces Cancel to Zero
• D. Unequal Length Arrows

Answer: (D)

Unbalanced forces show a net force acting on an object, so a force diagram will depict arrows that don’t cancel each other out. Each force is drawn with an arrow whose length represents its size; when the forces are unbalanced, the arrows have unequal lengths (and directions) so that their vector sum isn’t zero. The longer or dominant arrows pull in their direction, creating a net force that causes acceleration in that direction. If the forces were balanced, the arrows would effectively cancel and the net force would be zero, which isn’t the case with unbalanced forces.