These plots are just examples The key point is that no matte

These plots are just examples. The key point is that no matter what values you use for Initial velocity and initial angle, the graph doesn\'t go below positive x axis. The solution is the variable time t for x and y in graph. Both x and y are functions of time t. So when you create a vector t, the range of the vector t could be from 0 to the t_max. You can come up with an equation to get the t_max which will be determined by initial velocity and initial angle. The increment of time t could be very small such as 0.01.You use the comment sign to describe your explanation of the equation and its meaning. So when I run your code, I will change initial values and I should be able to see all positive graphs.

Solution

function projectile_motion % This program is used to view the path & distance covered by a particle in % animated form. % % Execute function in command window it will prompt yout to enter values % required by program, after getting input parameters it will calculate the % equations for projectile motion then it will show the animated path and % distance covered by particle. % % Created by M M Zafar % Date 15.01.2010 %% Input Parameters for projrctile motion theta = input(\'Enter launch angle= \'); %Launch angle, theta (degrees) m = input(\'Enter mass of the body= \'); %Mass, m (grams) Fs = input(\'Enter constant force spring force= \'); %Constant force spring force, Fs (N) Ns = input(\'Enter number of springs= \'); %Number of springs, Ns LL = input(\'Enter distance over which force is applied= \'); %Distance over which force is applied, LL (mm) eta = input(\'Enter efficiency= \'); %efficiency, eta g = input(\'Enter acceleration due to gravity= \'); %Acceleration due to gravity, g (m/s^2) N = input(\'Enter no. of steps= \'); %% Calcultion for projectile motion V = sqrt(2.*Ns.*Fs.*LL.*eta./m); %Launch velocity, V (m/s) Vy = V.*sind(theta); %Vertical velocity component, Vy (m/s) Vx = V.*cosd(theta); %Horizontal velocity component, Vx (m/s) tmh = V.*sind(theta)./g; % Time to maximum height, tmh (seconds) ttotal = 2.*tmh; % Total travel time, ttotal (seconds) ymax = (V.^2).*(sind(theta).^2)./(2.*g); %Maximum height, ymax (m) xmax = (V.^2).*(sind(2.*theta))./g; %Maximum range, xmax (m) tinc = ttotal./N; %Time increment, tinc %% Preallocation of answer spaces time = zeros(N,1); %Preallocation for time xpos = zeros(N,1); %Preallocation for X-Position ypos = zeros(N,1); %Preallocation for Y-Position %% Loop for generation of time vector for l = 1:N-1 time(l+1) = time(l)+tinc; end %% Loop for generation of x-position & y-position vector for j = 1:N xpos(j) = time(j).*Vx; ypos(j) = V.*time(j).*sind(theta)-0.5.*g.*time(j).^2; end %% Loop for visualization of plot for k = 1:N hold all h = plot(time(k),xpos(k),\'p\',time(k),ypos(k),\'o\',... \'LineWidth\',2,\'MarkerEdgeColor\',\'g\',... \'MarkerFaceColor\',\'y\',\'MarkerSize\',2+k); pause(0.6) drawnow end %% Annotation of graph legend(\'Distance\',\'Path\',\'Location\',\'NorthWest\') title(\'Projetile Trajectory\',\'FontSize\',14,\'FontWeight\',\'Bold\',\'FontName\',\'Calibri\') ylabel(\'Distance(m)\',\'FontSize\',12,\'FontWeight\',\'Bold\',\'FontName\',\'Calibri\') xlabel(\'Time(s)\',\'FontSize\',12,\'FontWeight\',\'Bold\',\'FontName\',\'Calibri\') grid on