Solving for Seesaw Balance: Mass and Distance Relationship

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In the discussion about solving the seesaw balance problem, the key focus is on determining the positions of two children with different masses on a 3.0m seesaw. One child weighs 20.0kg and the other 28.0kg, with the seesaw's fulcrum in the center. The effective riding position is achieved when the moments about the fulcrum are equal, leading to the conclusion that one child must sit at the end while the other sits 2.14m from the fulcrum. The participants clarify that the condition for effective balance is when the output work equals the input work. Ultimately, understanding the relationship between mass, distance, and moments is essential for solving the seesaw problem effectively.
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[SOLVED] Simple Machines Proble,

Homework Statement


Two kids are riding on a seesaw that is 3.0m long with its fulcrum exactly in the middle. When one end touches the ground, the other end is 1.4m in the air. If one child has a mass of 20.0kg and the other is 28.0kg, which child sits at the end of the seesaw and how far in does the other child sit so they can ride the seesaw effectively? Assume 100% efficiency for the seesaw.



Homework Equations

[I'm not sure if all these are needed, but these are the equations we were given in this unit]
Wi = Fi x Di
Wo = Fo x Do
MA = Fo / Fi
IMA = Di / Do
%eff = Wo / Wi or MA / IMA



The Attempt at a Solution


Umm I know from class that the answer is x = 2.14 m , but I don't know how to get there.
The stuff I attempted is majorly messed. I know it's wrong but I have no clue what to do. I basically found the Di and Do for each kid and subtracted them or something. I'm not even sure anymore. Lol..
 
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When is the seesaw ridden effectively? Is that related to total moment about the fulcrum in any way?
 
When Fo is greater than Fi?
That might be it.

*edit* JUST KIDDING! It's actually that Wo has to be equal to Wi.
 
Last edited:
Right, but have you understood?
 
Lol, I guess I do now that I figured that out. Nevermind!
 

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