In[]:=
Manipulate[ Show[Graphics[{{GrayLevel[0.8],Circle[{0,0},1], Rectangle[{Cos[2Pit],Sin[2Pit]-ps},{2, Sin[2Pit]+ps}]},Brown, Rectangle[{2,-1-ps},{2.05,1+ps}],{Hue[1], Disk[{Cos[2Pit],Sin[2Pit]},ps]}}], PlotRange{{-1.2,2.2},{-1.2,1.2}}],{t,0, 1-.01,.01},{ps,.02,.1,.01}]
Out[]=
