I am facing a difficult question and can't find answers anywhere else. What on the left is a hydraulic ram, it's pushing the box in the centre to move upward, while the four-bar linkage attached on box C is designed to regulate the centre box's motion and make sure it moves on a desired path. Assume all parts are rigid bodies except the hydraulic ram. O1, O2, B and G's location are known. At this instant, the ram provides an upward force which counterbalances the weight of the box, and it also gives a force pointing rightward, which is 1500N. The question is asking for the forces on each bar of the four-bar linkage, ignore the forces due to acceleration. Looks simple right? Just static load analysis. But my question is, where does the 1500N apply to? Does it apply to point G and B at the same time at 1500N? Or it only apply to G at 1500N? Any help is appreciated. I am not asking for the solution of the question, just where the 1500N applies to. Thanks. Diagram is here

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    $\begingroup$ Paragraphing and schematic is essential ! $\endgroup$ Sep 21 '19 at 20:05
  • $\begingroup$ There is no 1500N. There are only total force vectors acting on the box B at the three points of attachment. These you can decompose into i,j components which must sum to zero. Additionally, you must sum the moments about some convenient point such as g to zero, and you know the angle of the three links, hence the proportion of i to j in each link. So that is six equations and six unknowns. But you need the location of the links on the box, and you haven't provided its length. $\endgroup$
    – Phil Sweet
    Sep 21 '19 at 23:21
  • $\begingroup$ F = 1500i + 12000j applied at an angle θ. $\endgroup$ Sep 22 '19 at 22:36

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