# v'(t) = 32 - 0.18v - 0.14v^1.8, Nonlinear drag, ejected baggage example # Luggage is ejected from an airplane with zero initial velocity. The nonlinear # drag due to air resistance and weight is 0.18v+0.14v^1.8. Find the terminal # velocity and solve at t=3 for v(t) using step size 0.25 and the three methods # of Euler, Heun, RK4. Make an accurate plot of v(t) on 032-0.18*v-0.14*v^(9/5); myplot:=p->plots[odeplot](p,0..3); solve(F(v)=0,v); # terminal velocity p1:=dsolve({de,v(0)=0},v(t),numeric,method=classical[foreuler],stepsize=0.25); p2:=dsolve({de,v(0)=0},v(t),numeric,method=classical[heunform],stepsize=0.25); p3:=dsolve({de,v(0)=0},v(t),numeric,method=classical[rk4],stepsize=0.25); p4:=dsolve({de,v(0)=0},v(t),numeric); # Values at t=3 p1(3),p2(3),p3(3),p4(3); # Plot p4 on 0