Point Mass model, Acceleration, Velocity and position using Euler approximation

Hi, I am really new in Matlab and I find myself a bit lost how to create the model I want.

I am trying to recreate an Acceleration event. my car has to accelerate from 0 to reach a distance of 75m

Then I want to plot the acceleration vs time, velocity and so on.

This is the basic code I use:

clear 
clc
close all
%Constants for Point Mass
  m=250 %kg
  A=1.1 %m^2
  C=1.91 %Drag Coefficient of the car
  rho= 1.225 %kg/m^3 (density of air)
  D=rho*C*A/2
  g=9.81 %m/s^2 (acceleration due to gravity)
    %Initial Conditions
    dt= .001 %s
    x(1)=0 %m
    v0=0 %m/s
    v=v0
    t(1)=0 
    %Start Loop
    i=1
    while min(x)< 75;
        a=-(D/m)*v^2;
        v=v+a*dt; 
        x(i+1)=x(i)+v*dt+.5*a*dt^2;
        t(i+1)=t(i)+dt;
        i=i+1;
        x(1)=x(i);
       
    end
    plot(t,a)
    xlabel('time (s)')
    ylabel('acceleration')
    title('acceleration')

It stays runnig forever and I can not see how I can fix it

Answer 1

[darova]

Here is the answer

    x(1)=0 %m  
    while min(x)< 75;

min(x) is always 0