(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A woman and a man support a non-uniform plank, AB of mass 10kg and length 4m. The woman holds the plank 1m from A and the man holds the plank at B. The vertical reaction provided by the woman is 56N find;

A) the vertical reaction force provided my the man

b) The position at which at which the weight of the plank acts measured from A.

2. Relevant equations

3. The attempt at a solution

I worked out the vertical reaction produced by the man which is 42N, but I am really stuck on question 'b' ...

the answer in my book says the center of mass is 2.29m from A,

I have drawn a diagram, can anybody please check it and let me know what's wrong with it?

also my moments equation is..

[tex] 56N \times 1m + 42N \times 4m = 98N (xm-3m) [/tex]

http://www.mathhelpforum.com/math-help/attachments/advanced-applied-math/9167d1228774308-mechanics-help-untitled.jpg [Broken]

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# Homework Help: Moments-calculate centre of mass

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