Final answer:
The length of an arrow representing a force vector indicates the strength of the force, while the direction the arrow points shows the actual direction of that force.
Step-by-step explanation:
In physics, when representing a force vector with an arrow, the length of the arrow indicates the magnitude or strength of the force, not the direction. The direction of the vector is instead shown by which way the arrow points. For instance, if using a scale where 1 cm represents 2 N, a 20 N force directed east would be shown as a 10 cm long arrow pointing to the right. The point, or head, of the arrow indicates the direction the force is acting in, while the tail serves as the starting point of the vector. It's important to remember that vectors must be accurately drawn with both correct magnitude and direction for a proper representation of physical quantities like force or electric fields.