Objects are sized appropriately
Tick marks on ramp
Adjustable zero-height level (for P.E.)
Boundary conditions at ends of ramp.
Friction vs. No Friction.
Labels near tips of arrows.
Thermal Energy computation has errors near v=0 regions.
Arrows should be offset (non-overlapping).
Screen turds with zero-potential graphic.
Force Arrow text appears at (0,0) sometimes.
Arrow text label centering fails for arrows at angles.
How is the transform being handled?
Factor out arrow names.
Ramp length should be parameter.
Graph friction/normal/gravity force as a function of angle?
Open boundaries? (Launch off the up-side, slide onto horizontal on the down-side?)
What should the ‘jack’ look like? (The thing that props up the ramp.) Stack of books?