I have done M1, M2, C1 C2 C3 & C4 (A level maths modules, M meaning mechanics and C meaning core/pure). In M2 we learnt how to predict how a particle moves under gravity when projected at an angle, and we always ignored air resistance. In C4 we have learnt how to integrate a whole range of functions. This is not homework or school work I wondered how to predict the movement of a particle if the air resistance WAS taken into account. So I tried to figure it out and I just need to know if I have done it right. Here is the [very simple] example: A particle of mass one kg is initially travelling at 10m/s, air resistance is equal to a tenth of its current velocity. Find its velocity in terms of time. I wrote: F = ma v/10 = a a = v/10 acceleration is also dv/dt so: dv/dt = v/10 1/v dv = 1/10 dt integrate both sides you get: ln(v) = t/10 + lnA v = Ae^(t/10) t = 0, v = 10 10 = Ae^0 so final answer is: v = 10e^(t/10) is this right? is there another way to do it?