Car Rolling Down a Slope and Stop horizontally Model

Car Rolling Down a Slope and Stop horizontally Model

http://weelookang.blogspot.sg/2014/10/car-rolling-down-slope-and-stop.html
variables: theta = 42.5 ; R = m*g*cos(90-theta); g = 7 ; f = 1.2;  R1 = m*g*cos(90-theta)+215 ; f1 =1.2; k =0.7;
fx = if(t<0.175,R*cos(90-theta)-f*cos(theta),if(vx<0,0,-f1-k*vx))
fy =if(t<0.175,-m*g+R*sin(90-theta)+f*sin(theta),if(t<0.180,-m*g+R1,0))
requires Tracker 4.8 and above
https://dl.dropboxusercontent.com/u/44365627/lookangEJSworkspace/lookangejss/02_newtonianmechanics_3dynamics/trz/carrollingdownaslopeandstophorizontallymodel.trz