pendulum

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The other thing that you can do is to attach the code and images in

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The animation you provided is not working.Please post it and post the link again here and then your assignment will be graded

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Graded by : Mehul Shah

hi sir

in this simple pendulum program i have learnt lot about how it changes its location for various times

also a pendulum bob placed infront of thread is quiet interesting

i have upload my damping images and paste a link of my animation below

clear all
close all
clc
%inputs
b = 0.5;
g = 9.81;
l = 1;
m = 1;
%initial condition
theta_0 = [0;5];
%initial displacement=0,initial velocity=3rad/sec
%time points
t_span = linspace(0,20,200);
%solve ODE
[results] = lsode(\'odefunc\',theta_0,t_span);
%plotting
figure(1)
plot(t_span,results(:,1),\'color\',\'r\')
hold on
plot(t_span,results(:,2),\'color\',\'g\')
xlabel(\'time\')
ylabel(\'plot\')
legend(\'displacement\',\'velocity\')
x = results(:,1);
ct = 1;
for i=1:length(t_span)
    x0 = 0;
    y0 = 0;
    p = [(1*sin(x(i))),(-1*cos(x(i)))];
    figure(2)
    pause(0.03);
    plot([x0 p(1)],[y0 p(2)],\'linewidth\',2)
    hold on
    plot([-0.2 -0.2 0.2 0.2 -0.2],[-0.02 0 0 0.02 0.02],\'linewidth\',3)
    plot(x0,y0,\'-o\',\'linewidth\',2,\'color\',\'y\')
    plot(p(1),p(2),\'r.\',\'markersize\',70,\'linewidth\',3,\'color\',\'g\')
    hold off
    axis([-1 1 -1 0]);
    ct=ct+1;
    xlabel(\'time\')
    ylabel(\'displacement\')
    title(\'simple pendulum motion\')
    grid on
    text=sprintf(\"pendulum_damped_ode%05d.png\",ct);
    saveas(gca,text)
end
function [dtheta_dt] = odefunc(theta,t)
      b = 0.5;
      g = 9.81;
      l = 1;
      m = 1;
      theta1 = theta(1);
      theta2 = theta(2);
      dtheta1_dt = theta2;
      dtheta2_dt = -(b/m)*theta2-(g/l)*sin(theta1);
      dtheta_dt = [dtheta1_dt,dtheta2_dt];
end

https://youtu.be/Krswc29WMX0

https://projects.skill-lync.com/projects/simple-pendulum-motion-22332