How to Balance a See-Saw with Different Weights?

Thread starter needhelp83
Start date Nov 11, 2006

AI Thread Summary

To balance a see-saw with a 67-kg adult and a 23-kg child on a 10-m board, the pivot point should be placed at 2.56 meters from the adult. The calculation involves setting the moments equal, resulting in the equation 67d = (10-d)23. Solving this gives d = 2.56 m, indicating the correct placement for balance. It's important to clarify where the distance d is measured from for accuracy. The setup and calculations appear correct for achieving equilibrium.

Nov 11, 2006

needhelp83

A 67-kg adult sits at one end of a 10-m board, on the other end of which sits his 23-kg child. Where should the pivot point be placed so the board (ignore its mass) is balanced?

67d=(10-d)23
67d=230-23d
90d=230
d=2.56 m

The fulcrum should be at 2.56 m

Have I set this up right

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Nov 11, 2006

radou

Homework Helper

Looks okay.

Nov 11, 2006

Hootenanny

Staff Emeritus

Science Advisor

Gold Member

Looks okay to me, although you should state where your distance d is to me measured from.

Edit: Too slow again

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