MOMENTSA uniform rod 8m long weighing 5kg is supported horizontally by 2 vertical parallel strings @ p & Q and @ distances of 2m and 6m from one end.Weights of 1kg,1.5kg and 2kg are attached at distances of 1m, 5m and 7m respectively from the same end.Find the tension in each vertical stingShow all diagrams and workings
First calculate the total weight of the rod plus the 3 weights. The tension in the two supporting strings needs to be equal to this. One equation with two unknowns is what that gives you. Then calculate the sum of the moments about some point - whatever seems convenient - and that must be equal to 0. If you add up these moments, the weight of the rod can be treated as a point force at its midpoint. If the force is being applied to the left or right of the point where you are calculating the moment, and if the force is being applied to the up or down of the eeofrce, keep signs consistent. This gives you a second equation in 2 unknowns. You now have two equations in two unknowns, so you should be able to get your answer. If you use the second equation to calculate the moments about the point where one of the strings is attached, it will make things simpler.
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