force1d:

add object graphics
add object selector
wiggle me
free body diagram
enable/disable friction
add force model values
internationalize
crash sounds should be proportional to momentum
add graphic for pusher
crashing into a wall causes continually applied force to not update (probably because update strategy was set to xdriven)

done:
added velocity indicator during collision
get playback panel
add force graph

Rotation:
refactor to use MotionModel.addTemporalVariable