This is an example of a parametric trajectory in 2D.

Feel free to change the parametric trajectory and explore the velocity and accelerations of the particle.[br][br][list][*][size=85][i]Since velocity and acceleration have different units than displacement the 'size' of the vectors superimposed on the same graph is arbitrary. You can adjust the scale using the sliders so you can easily see the directions the vectors point[/i][/size][/*][*][size=85][i]Use the time slider to run the object through the trajectory and notice the relative directions of the velocity and acceleration.[/i][/size][/*][*][size=85][i]When your ready, compose a different parametric trajectory. Why not model circular motion? How about a Lemiscate?[/i][/size][/*][/list]