This model represents a rigid beam resting on a fulcrum at its center. Loads may be placed at various locations on the beam. Each load may be designated as fixed or movable. Fixed loads may be of fixed or variable magnitude. Clicking the Action button calculates the location of the movable loads and magnitude of variable loads that will keep this system in static equilibrium. The results are reported on the free-body diagram. If your setup precludes a solution, the model will notify you.

Colored spots mark each end of the beam. We will refer to the beam-ends by color since we may find the beam in any orientation. You may change the beam angle by clicking on the green end and dragging it to a new angle or by entering a specific angle in degrees in the beam angle control. Actually to drag the beam to a new angle you may click on it anywhere, but when you try to drag it you will find that you have hold of the green end. You may edit any of the existing vectors by clicking on the label for that vector. You may add new vectors to the system by clicking the Vector button. The Clear button gives you the option of resetting this model to the initial conditions for the most recent run, of clearing all the vectors for a new model of your own design.

For details on the operation of the controls, see the Model Controls help page.