Added friction sliders.
Label for the PE zero-point.
Friction vs. No Friction.
Arrows (and labels) should be offset (non-overlapping).
Especially problematic for small force arrows.
Screen turds with zero-potential graphic.
Arrow text label centering fails for arrows at angles.
Bar graph titles hard to read.
The sky and earth are too short.
Text graphics still appear at (0,0) when moving the ramp.
How is the transform being handled?
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?
Ramp should be reversible?
Depiction of W=F.x? (Displacement vectors?)