«Программы к моделированию физических задач (Pascal)» - Практическая работа

2.3. Моделирование артиллерийской задачи

Программа 1.

program Pushka;

{$R-}

{$Q-}

const

k: Integer = 0;

dt : Extended = 0.01;

da : Real = Pi / 25;

E: Extended = 0.1;

g: Real = 9.81;

I: Integer = 0;

Flag: Boolean = False;

Beg: Boolean = False;

Path: string = 'C:\temp';

var

X0 : Extended;

Y0 : Extended;

X1, X2: Extended;

Y1, Y2: Extended;

a, V0, L: Real;

PathTemp: string;

Num: string;

First: Boolean;

F: Text;

begin

Writeln('задайте скорость и угол');

Readln(V0, L);

a := Pi / 20;

I := 1;

while a < PI / 2 do

begin

X0 := 0;

Y0 := 0;

First := True;

Beg := False;

Str(I, Num);

PathTemp := Path + Num + '.dat';

Writeln(PathTemp);

Readln;

Assign(F, PathTemp);

Rewrite(F);

X1 := V0 * Cos(a) * dt - k * dt;

Y1 := X1 * Sin(a) / Cos(a);

while not Beg do

begin

{ Writeln(F, X0: 4: 4, ' ', Y0: 4: 4);}

Writeln(X0: 4: 4, ' ', Y0: 4: 4);

X2 := (X1 * (2 + k * dt) - X0) / (1 + k * dt);

Y2 := (Y1 * (2 - k * dt) - Y0 - g * Sqr(dt)) / (1 - k * dt);

X0 := X1; Y0 := Y1;

X1 := X2; Y1 := Y2;

if not First then

begin

Beg := Y0 <= 0;

Flag := ((X0 < (L + E)) or (X0 > (L - E))) and Beg;

end

else First := False;

end;

if Flag then

begin

Writeln('a =', (a * 180 / Pi):3:2);

Beg := False;

First := True;

X0 := 0;

Y0 := 0;

X1 := V0 * Cos(a) * dt - k * dt;

Y1 := X1 * Sin(a) / Cos(a);

while not Beg do

begin

Writeln(F, X0: 4: 4, ' ', Y0: 4: 4);

X2 := (X1 * (2 + k * dt) - X0) / (1 + k * dt);

Y2 := (Y1 * (2 - k * dt) - Y0 - g * Sqr(dt)) / (1 - k * dt);

X0 := X1;

Y0 := Y1;

X1 := X2;

Y1 := Y2;

if not First then

begin

Beg := Y0 <= 0;

Flag := ((X0 < (L + E)) or (X0 > (L - E))) and Beg;

end

else First := False;

end;

{ Readln;}

end;

a := a + da;

Inc(I);

Close(F);

end;

end.

2.7. Столкновение упругих шаров

Программа 1.

PROGRAM Shary;

VAR

Vcx,Vx1,Vcy,V2x,m2,V1y,V2y,Vx10,Vi,Vc,L,Vxy,X1,Y1,

X2,Y2,Vxi,V10z,Vxz,Vx10z,Vy10,Vy10z,Vyi,Vx20,Vx20z,Vy20,

Vy20z,V20z,Vy1z,Vy2,Vx1z,V10x,Vx2,Vx2z,Vy2z,m1,w:real;

begin

m1:=1; m2:=2; Vx1:=3; V2x:=4; V1y:=5; V2y:=6; X1:=7;

X2:=8; Y1:=9; Y2:=10; w:= ;

Vx10z:=Vx10*cos(w);

Vy10z:=Vy10*sin(w);

Vx20z:=Vx20*cos(w);

Vy20z:=Vy20*sin(w);

Vcx:=(m1*Vx1+m2*V2x)/(m1+m2);

Vcy:=(m1*V1y+m2*V2y)/(m1+m2);

Vx10:=Vx1-Vcx;

IF L=1 THEN

Vi:={=(Vc*L)/L}(Vxy*(X2-X1)+Vcy*(Y2-Y1))/sqrt(sqr(X2-X1)+sqr(Y2-

Y1));{Vi-Ї а ««Ґ«м­ п};

Vxi:={=Vi*(X2-X1)/sqrt(X2-X1)}((Vxy*(X2-X1)+Vcy*(Y2-Y1))/(sqr(X2-

X1)+sqr(Y2-Y1)))*(X2-X1);

Vyi:={=Vi*(Y2-Y1)/sqrt(Y2-Y1)}((Vxy*(X2-X1)+Vcy*(Y2-Y1))/(sqr(X2-

X1)+sqr(Y2-Y1)))*(Y2-Y1);

V10z:=Vx10-2*Vxi;

Vx1z:=Vx10z+Vxy;

Vx10:=Vx1 - Vcx;

Vy10:=Vx1 - Vcy;

Vx20:=Vx2 - Vcx;

Vy20:=Vx2 - Vcy;

Vx10z:=Vx10 - 2*Vxi;

Vy10z:=Vy10 - 2*Vyi;

Vx20z:=Vx20 - 2*Vxi;

Vx20z:=Vx20 + 2*Vxi;

Vx1z:= Vx10z + Vcx;

Vy1z:= Vy10z + Vcy;

Vx2z:= Vx20z + Vcx;

Vy2z:= Vy20z + Vcy;

WRITELN (Vx1z:1:2,' ',Vx2z:1:2,' ',Vy1z:1:2, ' ',Vy2z:1:2);

readln

end.