Use Material is not Suited For: Stand-alone introduction to motion under the influence of a central force
The lack of units and the inability to separately set speed and radius, makes the simulation more difficult to understand than necessary for lower level students. The units used in the applet are consistent with SI units, but all the numerical values, except for t, are given without units. The red ball has m=1.
Though possible, quantitative analysis is difficult because of the lack of information about the direction of the vectors, and the inability to step through the motion to determine maximum and minimum points. More complete theory would be helpful for intermediate students. The default behavior of changing the hanging mass to maintain circular motion when r or v is changed is counter-intuitive,
and should be changed. The visual clue of enlarging the black dot is insufficient (and possibly confusing).
There are also some problems with the font and subscripts. Fg denotes the gravitational force, but here g represents a subscript. Mg is the mass times the gravitational acceleration. Fg = Mg is not a good way to typeset this equation. Although there is a fair amount of text accompanying the applet, it is not organized effectively, with applet instructions intermixed with physics.