How Does Moving Closer to the Fulcrum Affect Teeter-Totter Balance?

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Moving closer to the fulcrum affects the balance of a teeter-totter by changing the distances of the individuals from the pivot point. When a heavy person and a light person, initially balanced, each move 25 cm toward the fulcrum, the lighter person's end will go down due to the greater leverage effect of their distance from the fulcrum. The heavier person, being closer, exerts less torque compared to the lighter person who is now at a greater distance. This results in an imbalance favoring the heavier individual. The conclusion is that the lighter person's end will indeed go down.
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Homework Statement


Suppose that a heavy person and a light person are balanced on a teeter-totter made of a plank of wood. Each person now moves toward the fulcrum a distance of 25 cms. What effect will this have on the balance of the teeter-totter?
A) The heavy person's end will go down
B) The teeter-totter will remain in balance
C) The light person's end will go down
D) One cannot tell whether either end will rise or fall without knowing the relative mass of the plank
E) Only if the plank has significant mass will the light person's end go down


The Attempt at a Solution


Since the teeter-totter is initially in balance, the center of gravity is right on the fulcrum. When they move in, the lighter person's end will go down since being that it is in balance they are at different distances from the fulcrum. The lighter person, being farther away, will have a greater effect than the closer heavier person, so C, the lighter person's end will go down.

I'm not at all sure if this is right :confused:
 
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