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bobbarkernar
Feb6-07, 09:30 PM
1. The problem statement, all variables and given/known data

a small boat hangs from two davits one of which is shown in the figure. the tension in line ABAD is 369 N. Determine the moent about C of the resultant force Ra exerted on the davit at A

2. Relevant equations



3. The attempt at a solution
ok so first i took the 369N and multiplyed it by the unit vector
(2.4i-3.1j-1.2k)/(2.4^+3.1^2+1.2^2)^.5 and got (216,-279,-108)
ok then i took the cross product of (216,-279,-108) and (-2.4,0,0)when i did this i got (0,-259.2,670)but the i component shouldnt be zero please help

Tom Mattson
Feb7-07, 06:56 PM
That distance of 3.1 meters doesn't look like it's parallel to the y-axis, but you're treating it as though it is parallel to it. Is it supposed to be vertical?

AlephZero
Feb8-07, 05:07 AM
Also, if "line ABAD" means the rope is double between A and B (as in your figure) there are three forces of 369N at point A, not one.