MATLAB Work

function LAB05ex1

m = 1;                                   % mass [kg]

k = 9;                                   % spring constant [N/m]

omega0=sqrt(k/m);            

y0=0.4; v0=0;                            % initial conditions

[t,Y]=ode45(@f,[0,10],[y0,v0],[],omega0);  % solve for 0<t<10

y=Y(:,1); v=Y(:,2);                        % retrieve y, v from Y

figure(1); plot(t,y,'b+-',t,v,'ro-');    % time series for y and v

grid on;

%------------------------------------------------------

function dYdt= f(t,Y,omega0)

y = Y(1); v= Y(2);

dYdt = [v; -omega0^2*y];

function LAB05ex1a

m = 1;                         % mass [kg]

k = 9;                         % spring constant [N/m]

c = 1;                         % friction coefficient [Ns/m]

omega0 = sqrt(k/m);  p = c/(2*m);

y0 = 0.4; v0 = 0;              % initial conditions

[t,Y]=ode45(@f,[0,10],[y0,v0],[],omega0,p); % solve for 0<t<10

y=Y(:,1); v=Y(:,2);                         % retrieve y, v from Y

figure(1); plot(t,y,'b+-',t,v,'ro-');       % time series for y and v

grid on

%------------------------------------------------------

function dYdt= f(t,Y,omega0,p)

y = Y(1); v= Y(2);

dYdt = [v; ?? ];                     % fill-in dv/dt