Graphical Analysis In our study of kinematics , we have noted that a lot of useful information about motion can be gleaned from motion graphs such as x v.s. f and v v.s. f. VPython has built in features that allow us to make graphs of any quantities we wish . The syntax is remarkably simple . In order to make graphs of position and velocity , we need to initiate the graphical curve routine for each , like this : fi = gourve [color=color.red) gourve (color=color . blue) These lines need to be placed early in the code in order to initialize our graphs . Later in the code , we begin to calculate positions and velocities in our While loop . All we need do is add : fl . plot (t , I . y) f2 . plot (b , v . ") to the while loop . Each time the loop goes round , it will add the vertical position , vertical velocity and time to the graph . Add these lines to the basic free -fall code provided and see what the result looks like . You should get a very pleasing graph that matches the physical motion that is being calculated the initial city but