I am making a game that has some sort of physics equations, although heavily modified to make it work better. I am trying to find the maximum velocity of a ship according to these rules/steps: thrust = ((p*r)^0.5)*10 -where r is a constant (0.04) and p is the power (3.33x10^5 in this case) friction = f*v*a -where f is another constant (500), v is the velocity, and a is yet another constant (1.5 in this case) force = t-friction acceleration = force/mass (mass = 1403.14) velocity += acceleration Ok, so there are several steps involved to find the velocity, but I am trying to make an equation that can show the velocity at any point in time, assuming you are accelerating the whole time. This equation would also give me the maximum velocity. The problem I am having is that the equation would involve the previous y value, and I don't know how to put that into an equation. Somthing like y = y_previous + (107.457 - (750 * y_previous) / mass) Thanks for any help.