Initial Conditions
tsim := 10:
pxi := 5:
pyi := 5:
vxi := 0.1:
vyi := -1:
m := 1:
Fxi := 0:
Fyi := 0:

Fx(t) := Fxi;
Fy(t) := Fyi;



Acceleration of particle
ax(t) := Fx(t)/m;
ay(t) := Fy(t)/m;



Velocity of particle
vx(t) := int(ax(t), t=0..t) + vxi;
vy(t) := int(ay(t), t=0..t) + vyi;



Position of particle from origin
px(t) := int(vx(t), t=0..t) + pxi;
py(t) := int(vy(t), t=0..t) + pyi;



d(t) := sqrt(px(t)^2 + py(t)^2);
d2(t) := diff(d(t), t);



Force on particle
Fx(t) := d2(t);
Fy(t) := 0;