7.3.3 Loads The actual load vector that is generated by SetLoads can be directly accessed with Loads. Loads can be very useful for debugging a model because it is often possible to read the load expressions directly and relate them to the function of the model. The load inspection function. An option for Loads. If the Coordinates option is not specified, Loads returns forces that are generalized to the current velocity coordinate system. Since velocity in the current model is represented by {Xnd, Ynd,  nd} the returned loads are {Fx, Fy, M}, calculated about the local origin. Consider the 2D ladder-on-wall model of Section 7.3.2. Loads can be used to find the total load applied to the ladder resolved into a force applied to the origin of the ladder, and a moment. Here is the total load applied to the ladder.
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In all cases, the sum of the applied, reaction, and dynamic loads on any body must be zero. Since there are no dynamic loads in this model, the total reaction loads on all constraints must be equal to the total applied loads. Here is the total reaction load applied by the constraints to the ladder.
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The dynamic, or inertial, loads on the ladder are identically zero because there are no masses or moments of inertia defined. If there were, the dynamic loads would be functions of the model's acceleration variables, X3dd, Y3dd, and so on. Here are the inertial loads on the ladder.
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Note that the numerical sum of the loads is zero, but the algebraic terms are quite different. This basically shows part of the system of equations that was solved by SolveMech when the numeric values of the Lagrange multipliers were found.
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