This system models the equation of motion of a projectile in the horizontal (x) and vertical (y) directions, with a linear drag force. The drag is quantified by a drag coefficient C, which can be set by means of a slider.
Note that the equation has been made non-dimensional by measuring time in units of v_0/g, and distance in units of v_0^2/g. In these units, the acceleration due to gravity is simply 1. Also the "seconds" in the time axis of the graphs really means the time units defined here. Also in these units the initial speed is simply 1.
The inclination has been fixed at Pi/2. A later version will let this change with a slider.
One of the displays is y vs. x, which shows the trajectory of the projectile.