A balancing act.

An instructor gave each student in his class a meter stick. Each student begins an assignment with their hands held in front of their body just less then a meter apart and their palms facing each other. The meter stick will be resting flat, on the upper side of their outstretched index fingers. From this starting position where the meter sticks are supported at positions near each end, the students where asked to slowly and steadily move their hand toward each other in a slow motion clapping type movement. The goal of the exercise is to move their hand towards each other until they are touching and then move them outward until they once again reach a position very similar to the starting position, with the meter stick balancing on top of their fingers for the entire exercise. The students are not allowed to touch the meter stick, other then with their two index fingers which should be kept more or less straight and perpendicular to the sticks length throughout the exercise.

With this exercise the instructor is demonstrating which one of these principles?

A. Nothing at all! It is just a very simple exercise that is being used to take up a bit of time. Since the instruction has nothing else planed.

B. Demonstrates that most individuals will have a noticeable difference in the coefficient of friction values between their left hand and their right hand.

C. Demonstrates that many individuals do not have the fine motor skills to actually do this difficult exercise without practicing.

D. Demonstrates a very simple self governing mechanical system with a type of mechanical feedback.

E. Demonstrates that many students are awkward and clumsy and may have difficulty performing even a very simple task.

F. Demonstrates that many surfaces (including a meter stick) may have a natural nap or grain on their surface so that the coefficient of friction is notably greater in one direction when compared then the opposite direction.