A look at the various forces in DOPs and how they work. This tutorial covers all the major forces except for the vortex, bouyancy and fluid forces. It covers both basic aspects and some more advanced techniques (animated masks, using RBD object position to drive a magnet force).  This first part covers initial scene set up; the uniform force, and the difference between uniform and gravity forces. It looks at torque, and how to select which objects are affected by a force. It looks at how to vary a force using noise subdata. A project file containing some of the examples shown here is available from