Autodesk inventor frame analysis
It's quite simple, really. All parts must have their respective materials properly assigned. Then, you must use the "Ground" tool while in the "Structural Analysis" simulation tool. Ground the face opposite of where the force will be applied. Next, select force. Apply this on the face opposite of the grounded face. I then would recommend doing what Mr. Rinaldi recommended, and input force in that manner. Or, simply use the lb. unit when inputting force.