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

A horizontal piece of wood that has a weight 40N is held in equilibrium by two brackets, A and B. The wood is 1.6m long (CD). A is 0.4m from C and B is 0.2m from D. Meaning that there is 1.0m between A and B. At rest the reaction force at A is 24 N and at B 16N. When an object is put on the wood at xm from C, show that the vertical reaction force on the shelf at A is (24-W(x-1.4))N

2. Relevant equations

Moment=Force x Distance

3. The attempt at a solution

I understand that the W(x-1.4) is the moment of the object but I cant seem to get the 24.

If taking moments about B:

(x-1.4)W + (24 x 1) = 40 x 0.6

which isn't right

Any help at all would be greatly appreciated. many thanks.

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# Homework Help: Proving what the reaction force equals with moments in mechanics.

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