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Homework Statement
Two plasterers Bill and Dave of mass 45kg and 65kg respectively stand on a unofrm plan ABCDEF of length 4m and mass 40kg. The plank is supported at C and E where C is 1m from A and E is 1m from F. Plasterer Bill stands at B which is 0.5m from A and plasterer Dave stands at D which is 1.5m from F.
a) Draw a diagram showing the above information
b) Find the reaction at each support, giving your answers in N to 1 decimal place.
Homework Equations
http://img164.imageshack.us/img164/9263/drawnqf5.jpg
I drew this on paint, seems to be correct. Thats a) done.
The Attempt at a Solution
The question dosen't state anything about Equilbirum, but here's what I done:
m(R):
0.5 x 45g + S = 40g + 1.5 x 65g
S = 40g + 97.5g - 22.5g
S = 1127N
Sub this into:
S + R = 150g
R = 150g - 1127
R = 343N.
However they are both completely wrong, I assume I am going wrong with thinking it is in equilbrium. Since it isn't, I'm not too sure on where to start.
Any hints/help is very appreciated =)!
Thank you.
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