AGAINST THE WALL
INTRODUCTION The center of balance or center
of gravity of an object is the point in that object at which you can
consider all of its mass to be concentrated. This point is also called
the balancing point because the object will balance when supported at that
point. We first saw this activity in a book by Rowe and Perham.1 It is
most useful for grades 2-6 or even for adults and is especially effective
for introducing the topic of center of balance or center of gravity. PURPOSE The purpose of this activity is
to try to balance your body on two legs or on only one leg when tight
against the wall.. MATERIALS
PROCEDURE
EXPLANATION
In the case with your left side against the wall, the center of balance of your body is between the wall and your right foot when you raise your left foot (try to picture that). Thus, your center of balance is supported between the wall and your right foot.
However, when you raise your right foot, your center of balance is now outside both the wall and your left foot, you cannot maintain balance (unless you cheat and move your feet farther from the wall), and you fall over to your right.
The reverse processes occur when you place your right side tight against the wall. You can maintain balance when your right foot is raised, but not when your left foot is raised. ADDITIONAL SUGGESTIONS
Repeat the above procedure with your arm away from the wall extended straight out from the wall. What happens in all sets of circumstances, left side to the wall, right side to the wall, with right foot raised, and with left foot raised? Why? Where is your center of balance with your arm extended?
REFERENCES
|
||||||
