Acceleration determined by force and mass

A simple, but profound truth

We've moved from a lived-in world, perhaps of the everyday, perhaps of the remote, to an environment which is natural for un-skinned objects. Here the only property the object retains is its mass: everything else is lost in the process of the extraction.

Acting on the mass are forces. We've identified the forces by looking at the environment. Particular facets of the lived-in world interact with the object in ways that result in these facets being said to exert forces on the object. These forces are all that's left of the environment that the object left behind.

The forces acting on a single object can be added to give a resultant. Now you've an even simpler world where there is only an object, which has a mass, and a single force acting on it. It's now simple enough that you can predict changes in its motion, using:

acceleration = forcemass

How this acceleration affects the velocity and the motions that result are the subject of the next episode.