CÁC BÀI TOÁN NGUỘI CỦA CỐC CAFEVD1: Xac dinh các tham so trong qua trinh nguoi cua coc cafe den bang phuong phap xap xi ham phi tuyen... VD5: Mo phong Monte-Callor quy luat phan huy hat
Trang 1CÁC BÀI TOÁN NGUỘI CỦA CỐC CAFE
VD1: Xac dinh các tham so trong qua trinh nguoi cua coc cafe den bang phuong
phap xap xi ham phi tuyen
Phuong trinh : dT/dt=-r(T-Tf)
-o0o -% Gan so lieu
clc;clear all;close all;
ti=0:2:46; % Thoi gian do
nTf=17; % Nhiet do phong
Tcd=[82.3 78.5 74.3 70.7 67.6 65.0
62.5 60.1 58.1 56.1 54.3 52.8
51.2 49.9 48.6 47.2 46.1 45.0
43.9 43.0 41.9 41.0 40.1 39.5 ]; % Nhiet do thuc nghiem
% Giai phuong trinh nguoi
T=dsolve('DT=-r*(T-Tf)','T(0)=T0','t');
disp('Bieu thuc T tinh duoc:'); pretty(T)
%Tinh gia tri va ve do thi cua coc cafe den
title('Qua trinh nguoi cua coc cafe den');
xlabel('Thoi gian(phut)'); ylabel('Nhiet do (C)');
legend('So lieu tinh','So lieu do');
Qua trinh nguoi cua coc cafe den
VD2: Xac dinh cac tham so trong qua trinh nguoi cua coc cafe den bang xap xi
ham phi tuyen
Phuong trinh : dT/dt=-r(T-Tf)^2 -o0o -
% Gan so lieuclc;clear all;close all;ti=0:2:46; % Thoi gian donTf=17; % Nhiet do phongTcd=[82.3 78.5 74.3 70.7 67.6 65.0
62.5 60.1 58.1 56.1 54.3 52.8
51.2 49.9 48.6 47.2 46.1 45.0
43.9 43.0 41.9 41.0 40.1 39.5 ]; % Nhiet do thuc nghiem
% Giai phuong trinh nguoiT=dsolve('DT=-r*(T-Tf)^2','T(0)=T0','t'); %Tim no giai tich cua ptvp thuongdisp('Bieu thuc T tinh duoc:'); pretty(T)
%pretty:Bieu dien dang tu nhien cua bien sym
1
Trang 2%Tinh gia tri va ve do thi cua coc cafe den
title('Qua trinh nguoi cua coc cafe den');
xlabel('Thoi gian(phut)'); ylabel('Nhiet do (C)');
legend('So lieu tinh','So lieu do');
62.5 60.1 58.1 56.1 54.3 52.8
51.2 49.9 48.6 47.2 46.1 45.0
43.9 43.0 41.9 41.0 40.1 39.5 ]; % Nhiet do thuc nghiem
% Giai phuong trinh nguoiT=dsolve('DT=-r(2)*(T-Tf)^2-r(1)*(T-Tf)','T(0)=T0','t');
disp('Bieu thuc T tinh duoc:'); pretty(T)
%Tinh gia tri va ve do thi cua coc cafe densyms r1r2
T12=subs(T,{'r(1)','r(2)'},{r1,r2});
disp('T12='); pretty(T12)T1=limit(T12,r2,0);
disp('T1='); pretty(T1)
2
Trang 3T2=limit(T12,r1,0); %Tinh gioi han cua T12
plot(ti,Tcd,'o',ti,(f(r1201,ti)),'.-');
title('Mo hinh dT/dt=-r_1.(T-Tf)');
xlabel('t-min'); ylabel('T (C)'); grid on;
legend('So lieu tinh','So lieu do');
figure(2);
plot(ti,Tcd,'o',ti,(f(r1202,ti)),'.-');
title('Mo hinh dT/dt=-r_2.(T-Tf)^2');
xlabel('t-min'); ylabel('T (C)'); grid on;
legend('So lieu tinh','So lieu do');
figure(3);
plot(ti,Tcd,'o',ti,(f(r12,ti)),'.-');
title('Mo hinh dT/dt=-r_1.(T-Tf)-r_2.(T-Tf)^2');
xlabel('t-min'); ylabel('T (C)'); grid on;
legend('So lieu tinh','So lieu do');
% -End -r12 = 0.0074 0.0004
35 40 45 50 55 60 65 70 75 80 85
disp('Bieu thuc T tinh duoc:'); pretty(T)
%Tinh gia tri va ve do thi cua coc cafe densyms rT0TfPt
plot(ti,Tcd,'o',ti,(f(Pn,ti)),'.-');
Trang 4title('Mo hinh dT/dt=-r_1.(T-Tf)');
xlabel('t-min'); ylabel('T (C)'); grid on;
legend('So lieu tinh','So lieu do');
% Giai phuong trinh nguoi dT/dt=-r2(T-Tf)^2
plot(ti,Tcd,'o',ti,(f(Pn,ti)),'.-');
title('Mo hinh dT/dt=-r_2.(T-Tf)^2');
xlabel('t-min'); ylabel('T (C)'); grid on;
legend('So lieu tinh','So lieu do');
% -End -0 5 10 15 20 25 30 35 40 45 50 35
40 45 50 55 60 65 70 75 80 85
40 45 50 55 60 65 70 75 80 85
Trang 5CÁC BÀI TOÁN PHÂN HỦY HẠT NHÂN
VD1:
-o0o -function box1;
close all; clc;
N=1000; dt=N/10; t=0:10*N; % N-so hat trong hop
n=zeros(size(t)); n(1)=N; %Tao mang co kich thuoc t co cac ptu =0
400 500 600 700 800 900
1000
ngiai tichN/2 n
mo phong
VD2:
function nucdecay1;
-o0o -clc;clear all;close all;
% Mo phong Monte-Callor quy luat phan huy hat nhan
% theo phan bo Poisson
Trang 6global ntrial; figure(fig);
n=0:max(nn); np=hist(nn,n); Pi=np/ntrial; %hist=>tinh tan so cua mau
m=mean(nn); s2=var(nn);
subplot(2,1,1); bar(n,np); xlim([0 n(end)]);
title(['Tan so phan huy sau ',
hold on; plot(n,Plt,'.r-'); hold off;
title(['Phan bo Poisson voi < n > = ',
num2str(m)])
0 500 1000 1500 2000
Tan so phan huy sau 1 dvtg
0 0.05 0.1 0.15 0.2
Phan bo Poisson voi < n > = 5.0085
0 500 1000
1500
Tan so phan huy sau 2 dvtg
0 0.05 0.1 0.15 0.2
Phan bo Poisson voi < n > = 9.9415
VD3: Mo phong Monte-Callor phan huy hat nhan
clear; clc; close all;
-o0o -N0=10; % N0 -So hat nhan khong ben luc daup=0.01; % p -Xac suat phan huy
tmax=500; % tmax -Khoang thoi gian khao satntrial=200; % ntrial -So lan thu
ti=1:tmax; ncum=zeros(1,tmax);
for k=1:ntrial N=ones(1,N0);
ti=[0 ti]; ni=[N0 ni];
ni_gt=N0*exp(-p*ti);
h=plot(ti(1),ni(1),'r',ti,ni_gt,'b');
legend('ni_{mo phong}','ni_{giai tich}');
6
Trang 7-o0o -clear; clc; close all;
N0=5000; % -So hat nhan khong ben luc dau
p1=0.01; % -Xac suat phan huy h/n ng/to 1
p2=0.005; % -Xac suat phan huy h/n ng/to 2
% tmax: -Khoang thoi gian khao sat
% ntrial: -So lan thu
ncum1(t)=ncum1(t)+sum(N1);
ncum2(t)=ncum2(t)+sum(N2);
endendni1=ncum1/ntrial;
5000
n1i
mphong
n1igtichn2imphongn2igtich
7
Trang 8VD5: Mo phong Monte-Callor quy luat phan huy hat nhan
Theo quy luat ham mu
-o0o -clc; close all;
N0=2000; % N0-So hat nhan khg ben luc dau
p=0.01; % p-Xac suat phan huy
tmax=200; % khoang thoi gian quan sat
ntrial=1; % ntrial-So lan thu
ti=[0 ti]; ni=[N0 ni];
ni_gt=N0*exp(-p*ti); %Cong thuc giai tich
VD6: Mo phong Monte-Callor quy luat phan huy hat nhan
Ngto pxa 1(me) > ngto pxa 2(con) Khi bi pra >ngto ben vung -o0o -clc; close all; close all;
N0=2000; % N0-So hat nhan khg ben luc daup1=0.01; % Xac suat phan huy hat nhan gto 1(me)p2=0.005; % Xac suat phan huy hat nhan gto 2(con)tmax=500; % khoang thoi gian quan sat
ntrial=1; % ntrial-So lan thuti=1:tmax;
ncum1=zeros(1,tmax);
ncum2=ncum1;
for k=1:ntrial N1=ones(1,N0);
N2=zeros(1,N0);
for t=1:tmax r1=rand(size(N1));
r2=rand(size(N2));
N3=N1&(r1<=p1); %So hat nhan me bi phan huy thanh hat nhan con N1=N1&(r1>p1); %So hat nhan me ko bi phan huy thanh hat nhan con N2=N2&(r2>p2); %So hat nhan con ko bi phan huy
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Trang 9ti=[0 ti]; ni1=[N0 ni1];ni2=[N0 ni2];
ni1_gt=N0*exp(-p1*ti); %Cong thuc giai tich
ni2_gt=N0/(p1-p2)*p1*exp(-p2*ti)-N0/(p1-p2)*p1*exp(-p1*ti);
plot(ti,ni1,'r',ti,ni1_gt,'b',ti,ni2,'k',ti,ni2_gt,'g');
legend('n1i_{mo phong}','n1i_{giai tich}','n2i_{mo phong}','n2i_{giai tich}');
0 200 400 600 800 1000
eqs=[eq1,',',eq2,',',eq3];
ints='NKr(0)=1,NBr(0)=0,NSe(0)=0'; %Dieu kien ban daudsol=dsolve(eqs,ints);
title('Qua trinh phan huy phong xa nguyen to Kr');
xlabel('Thoi gian/h'); ylabel('Khoi luong/mg')
% -End -0 20 40 60 80 100 120 140 160 180 200 0
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
CÁC BÀI TOÁN CHUYỂN ĐỘNG
9
Trang 10VD1: Qua bong nem xien 40 do
subplot(2,1,1); ezplot(x1,y1,[0 tn]); title('Quy dao y(x)'); grid on;pause;
% % Hinh anh chuyen dong -
-End -10
Trang 11t y1(t)
t Vy1(t)
c=menu('Chon :','Nhap Vth','Hinh ch/dg');
switch c case 1nvt=input('Nhap van toc toi han vt=');
xlim([-.2 9]); xlabel('t-Thoi gian (s)');
ylabel('y-Vi tri (m)');
title('Qua cau xop roi co tinh den ma sat');
case 2 disp(['Van toc Vt2=',num2str(nvt)]) break;
endend
11
Trang 12% Van toc va gia toc
-figure(2);
subplot(1,2,1); plot(ti,vy,'.-');
xlim([-.2 9]); xlabel('t-Thoi gian (s)');
ylabel('Vy-Van toc (m/s)');
pp=spline(ti,vy);
pp1=fnder(pp); %Dao ham he da thuc bac n
subplot(1,2,2); plot(ti,ppval(pp1,ti),'.-');
xlim([-.2 9]); xlabel('t-Thoi gian (s)');
ylabel('Ay-Gia toc (m/s^2)');
-End -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 -3.5
-3 -2.5 -2 -1.5 -1 -0.5 0
-6 -5 -4 -3 -2 -1 0
-9 -8 -7 -6 -5 -4 -3 -2
Trang 13clear all; close all; clc
% Chu y khi k1=10,k1=0 bieu thuc suy bien
% Nen dung ham limit thay ham subs
for k=1:4 ve=vek(k); cl=clk(k);
z2=subs(z1); z2=subs(z2,t,gtt);
vz2=subs(vz1); vz2=subs(vz2,t,gtt);
subplot(2,2,1); plot(gtt,z2,cl); hold on; title('Do thi z(t)'); grid on; subplot(2,2,3); plot(gtt,vz2,cl); hold on; title('Do thi Vz(t)'); grid on; subplot(1,2,2);plot(z2,vz2,cl);hold on; title('Do thi Vz(z)'); grid on; lg{k}=(['ve=',num2str(ve)]);
endlegend(lg);
% d Truong hop khi Fms=k2*Dz^2D2z=solve(pt32,D2z);
dz1=inline(['[z(2);',char(D2z1),']'],'t','z');
[t,z]=ode45(dz1,[0 double(tf1)],[0 0]);
subplot(2,2,1); plot(t,z(:,1),clk(k)); hold on; title('Do thi z(t)'); grid on; subplot(2,2,3); plot(t,z(:,2),clk(k)); hold on; title('Do thi Vz(t)'); grid on; subplot(1,2,2); plot(z(:,1),z(:,2),clk(k)); hold on; title('Do thi Vz(z)'); grid on; lg{k}=(['ve=',num2str(vek(k))]);
endlegend(lg);
-End -13
Trang 140 200 400 600 800 1000
1200
Do thi Vz(z)
ve=100 ve=200 ve=300 ve=400
0 100 200 300 400 500
600
Do thi Vz(z)
ve=100 ve=200 ve=300 ve=400
VD4: Chuyen dong cua cac hanh tinh
function planet1
-o0o -%Program planetclose all;clc;
%Lz=x.*vy-y.*vx; % ======Mo men dg lg/m: Lz/m=x*vy-y*vx
%====================Bieu dien do thilim=1.2*[min(x),max(x),min(y),max(y)];
figure(1);
plot(x,y,vx,vy); grid on; axis equal; title('Quy dao hanh tinh');
xlabel('x, vx'); ylabel('y, vy'); legend('Toa do','Van toc');
figure(2);
subplot(2,1,1); plot(t,x,t,y,t,r); legend('x(t)','y(t)','r(t)'); xlabel('t'); grid on
subplot(2,1,2); plot(t,vx,t,vy,t,v); legend('vx(t)','vy(t)','v(t)'); xlabel('t'); grid on
figure(3);
subplot(2,1,1); plot(t,r,t,v,t,phi); legend('r(t)','v(t)','phi(t)'); xlabel('t'); grid on
subplot(2,1,2); plot(t,Ek,t,Eu,t,E,t,Lz); legend('Ek(t)','Eu(t)','E(t)','Lz(t)');
14
-2 -1 0 1 2 3 4 5 6 7
Quy dao hanh tinh
Toa do Van toc
-5 0 5 10
t
r(t) v(t) phi(t)
-40 -20 0 20 40
t
Ek(t) Eu(t) E(t) Lz(t)
-2 -1.5 -1 -0.5 0 0.5 1 1.5 2
Trang 15set(h(2),'erase','non');
set(h(3),'markersize',50);
axis equal; axis(lim);
xlabel('x'); ylabel('y');
-o0o -%Program planeclear all; close all; clc;
Lz=x.*vy-y.*vx; % -<Mo men xung luong>/m: Lz=x*vy-y*vx
% -Bieu dien do thilim=1.2*[min(x),max(x),min(y),max(y)];
-2 0 2 4 6
Toa do Van toc
-4 -2 0 2 4
x(t) y(t) r(t)
-10 -5 0 5
10
vx(t) vy(t) v(t)
-4 -2 0 2 4
t
x(t) y(t) r(t)
-10 -5 0 5 10
t
vx(t) vy(t) v(t)
Trang 16figure(1); shg
plot(x,y,vx,vy); grid on; axis equal; legend('Toa do','Van toc');
figure(2);
subplot(2,1,1); plot(t,x,t,y,t,r); legend('x(t)','y(t)','r(t)'); grid on
subplot(2,1,2); plot(t,vx,t,vy,t,v); legend('vx(t)','vy(t)','v(t)'); grid on
figure(3);
subplot(2,1,1); plot(t,Ek,t,Eu,t,E); legend('Ek(t)','Eu(t)','E(t)'); grid on
subplot(2,1,2); plot(t,E,t,Lz); legend('E(t)','Lz(t)'); grid on
% -Hinh anh chuyen dong
set(h(1),'erase','xor','markersize',20);
set(h(2),'erase','non');
-o0o -clc; clear all; close all;global GM Gm1 Gm2; % GM=G*M; Gm1=G*m1; Gm2=G*m2;
GM1=4*pi^2; dt=.01;
k=menu('Chon:','He mat troi 1','He mat troi 2','Thoat');
switch k case 1GM=GM1;
16
-40 -20 0 20
40
Ek (t) Eu(t) E(t)
-10 -5 0 5
10
E(t) Lz(t)
-3.5 -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5
Trang 17axis equal;axis([-4 4 -4 4]);
title('He "Nhat tam"'); xlabel('x'); ylabel('y');
h1=plot(xi(1),yi(1),':g',xi(2),yi(2),':b');
figure(2);
plot(0,0,'.b','markersize',20); hold on;
h2=plot(xi(1)-xi(2),yi(1)-yi(2),'.g',-xi(2),-yi(2),'.r');
axis equal; axis([-4 4 -4 4]);
title('He "Dia tam"'); xlabel('x'); ylabel('y');
set(h(1),'xdat',xi(1),'ydat',yi(1));
set(h(2),'xdat',xi(2),'ydat',yi(2));
set(h1(1),'xdat',x(:,1),'ydat',y(:,1));
set(h1(2),'xdat',x(:,2),'ydat',y(:,2));
set(h2(1),'xdat',xi1(1),'ydat',yi1(1));
set(h2(2),'xdat',xi1(2),'ydat',yi1(2));
set(h3(1),'xdat',x1(:,1),'ydat',y1(:,1));
set(h3(2),'xdat',x1(:,2),'ydat',y1(:,2));
pause(.01);
end;
function [xi,yi,vxi,vyi]=tinh(x0,y0,vx0,vy0,dt);opt=odeset('reltol',1e-3,'abstol',1e-4);
% -u0=[x0(:); y0(:); vx0(:); vy0(:)];
% -global GM Gm1 Gm2r1=sqrt(u(1)^2+u(3)^2);
Trang 18-GM*u(2)/r2^3-Gm1*(u(2)-u(1))/r12^3;
-GM*u(3)/r1^3-Gm2*(u(3)-u(4))/r12^3;
-GM*u(4)/r2^3-Gm1*(u(4)-u(3))/r12^3];
-End -CÁC BÀI TOÁN DAO ĐỘNG
VD1: Dao dong dieu hoa
Ko co ngoai luc -o0o -function daodgtdh0;
% Program dao dong tu tuyen tinh
% khong co ngoai lucclc;close all
18
Trang 19% Truong hop rieng voi cac tham so cu the
% - Khong ma sat, dao dong bao toan
% - Co ma sat, dao dong tat dan
-gtri2={gtw 0 1 0 0.2};% gia tri tham so
subplot(2,1,1); plot(t1,gtx1,t1,gtv1); grid on;
title('Dao dong dieu hoa'); legend('x(t)','v(t)');
subplot(2,1,2); plot(t1,gtx2,t1,gtv2); grid on;
title('Dao dong tat dan'); legend('x(t)','v(t)');
% The nang,dong nang va nang luong tong
-plot(gtx1,gtv1,gtx2,gtv2); grid on; xlabel('x'); ylabel('v');
legend('Dieu hoa','Tat dan'); title('Dao dong trong khong gian pha');
% Hinh anh chuyen dong figure(4);
-subplot(2,1,1); chdgdh(gtx1); %goi ham chdgdhsubplot(2,1,2); chdgdh(gtx2);
function chdgdh(x0);
% -plot([-4 -4],[3 0],'linewidth',6); grid on; hold on; xlim([-4 4]);
t=linspace(-pi,10*pi,200);
xx=.25*cos(t)-3.25+(2+x0(1))*(t+pi)/(11*pi);
x=[-4 xx (xx(end)+.52)];
y=.5*[1 sin(t)+1 1];
h1=plot(x,y,'linewidth',3,'erase','xor');
h2=plot(x0(1),.5,'s','markersize',47,'markerfacecolor','r','erase','xor');
19
Trang 200 1 2
3
Dao dong dieu hoa
Ep(t) Ek(t) Et(t)
0 1 2
3
Dao dong tat dan
Ep(t) Ek(t) Et(t)
-2 -1.5 -1 -0.5 0 0.5 1 1.5 2
x
Dao dong trong khong gian pha
Dieu hoa Tat dan
20
Trang 21VD2: Program dao dong tu dieu hoa
Ep1=gtw^2*gtx1.^2/2; %Dong nang
Ek1=gtv1.^2/2; % The nangEt1=Ep1+Ek1; % Nang luong
% Co ma sat gtri2={gtw gtw1 0 0 0.2 5};
-x2=subs(x,{w,w1,x0,v0,b,c},gtri2); x2=simple(x2)v2=subs(v,{w,w1,x0,v0,b,c},gtri2); v2=simple(v2)fx2=inline(vectorize(x2),'t'); gtx2=fx2(t1);
fv2=inline(vectorize(v2),'t'); gtv2=fv2(t1);
Ep2=gtw^2*gtx2.^2/2; %Dong nangEk2=gtv2.^2/2; % The nang
Et2=Ep2+Ek2; % Nang luong
% Bieu dien do thi
% Ly do, van toc figure(1);
-subplot(2,1,1); plot(t1,gtx1,t1,gtv1); grid on;legend('x(t)','v(t)'); title('Dao dong co ngoai luc khg ma sat');
subplot(2,1,2); plot(t1,gtx2,t1,gtv2); grid on
legend('x(t)','v(t)'); title('Dao dong co ngoai luc co ma sat');
% The nang,dong nang va nang luong tong figure(2);
subplot(2,1,1); plot(t1,Ep1,t1,Ek1,t1,Et1); grid on; legend('Ep(t)','Ek(t)','Et(t)'); title('Dao dong dieu hoa');
subplot(2,1,2); plot(t1,Ep2,t1,Ek2,t1,Et2); grid on;legend('Ep(t)','Ek(t)','Et(t)'); title('Dao dong tat dan');
% Khong gian pha figure(3);
-plot(gtx1,gtv1,gtx2,gtv2); grid on; xlabel('x');ylabel('v');
legend('Khong ma sat','Co ma sat'); title('Dao dong co ng/luc trg khg gian pha');end %while
-End -21
-1 -0.5 0 0.5 1
Dao dong co ngoai luc khg ma sat
-1 -0.5 0 0.5 1
Dao dong co ngoai luc co ma sat
x(t) v(t)
x(t) v(t)
0 0.2 0.4 0.6 0.8
Dao dong dieu hoa
0 0.2 0.4 0.6 0.8
Dao dong tat dan
Ep(t) Ek(t) Et(t)
Ep(t) Ek(t) Et(t)
Trang 22%Tham so xac dinha1=1.5; w1=1.8; phi1=3;
a2=1.3; w2=1.5; phi2=2;
k=1; k1=1; x=0; y=0; t=0; dt=0.1; p=.03;
%Tao cua so dieu khien va cac phim dieu khienuicontrol('position',[20 20 60 20],
'string','Thoat','callback','k=0;k1=0;')
%unicontrol=>tao giao dien ng/dung de dieu khien doi tuonguicontrol('position',[20 50 60 20],
'string','Dung','callback','k1=1;')uicontrol('position',[20 80 60 20],
'string','Chay','callback','k1=0;')h=plot(x,y,'g','linewidth',2); grid on; axis equal;axis([-2.2 2.2 -2.2 2.2]); set(gca,'color',[0 3 0]);
title('Tong hop 2 dao dong dieu hoa vuong goc');
%Trang thai dung ban dauwhile k1; pause(0.1); end;
%Bat dau chayx=a1*sin(w1*t+phi1); y=a2*sin(w2*t+phi2);
22
Trang 23-2 -1.5 -1 -0.5 0 0.5 1 1.5 2 -2
-1.5 -1 -0.5 0 0.5 1 1.5 2 Tong hop 2 dao dong dieu hoa vuong goc
VD4: Chuong trinh he 2 dao dong tu dieu hoa
subplot(2,1,1); ezplot(x13,[0 30]); grid on;title('Do thi x1(t) khi Dkd phuc tap');
subplot(2,1,2); ezplot(x23,[0 30]); grid on;title('Do thi x2(t) khi Dkd phuc tap');
23
Trang 24Do thi x2(t) khi Dkd phuc tap
VD5: Con lac phi tuyen
function conlacphituyen
-o0o -% Program dao dong con lac phi tuyen
% khong co ngoai lucclc;close all
% - Co ma sat, dao dong tat dan sm0=subs(st0,{g,L,b},{g0,L0,b2});
Trang 25% Bieu dien do thi
% - Goc, van toc goc
-figure(1);
subplot(2,1,1); plot(t1,th1,t1,dth1); grid on;
legend('\theta(t)','\theta''(t)'); title('Dao dong bao toan');
subplot(2,1,2); plot(t1,th2,t1,dth2); grid on;
legend('\theta(t)','\theta''(t)'); title('Dao dong tat dan');
% - The nang,dong nang va nang luong tong
figure(2);
subplot(2,1,1);plot(t1,Ep1,t1,Ek1,t1,Et1); grid on;
legend('Ep(t)','Ek(t)','Et(t)'); title('Dao dong bao toan');
subplot(2,1,2); plot(t1,Ep2,t1,Ek2,t1,Et2); grid on;
legend('Ep(t)','Ek(t)','Et(t)'); title('Dao dong tat dan');
% - Khong gian pha
-figure(3);
plot(th1,dth1,th2,dth2); grid on; xlabel('\theta'); ylabel('\theta''');
legend('Bao toan','Tat dan'); title('Dao dong trong khong gian pha');
% % - Hinh anh chuyen dong
VD6: Con lac kép
function conlackep
-o0o -25
-4 -2 0 2 4
Dao dong bao toan
-4 -2 0 2
Dao dong tat dan
0 2 4 6 8 10 12 14 16 18 20 0
5 10 15 20
Dao dong bao toan
Ep(t) Ek(t) Et(t)
0 2 4 6 8 10 12 14 16 18 20 0
5 10 15 20
Dao dong tat dan
Ep(t) Ek(t) Et(t)
-4 -3 -2 -1 0 1 2 3 4
0 0.5 1 1.5 2
Dao dong tat dan