The formula for drag force can be found anywhere really. FD = 0.5 * ρ * v2 * A * CD; that is, Frictional Drag equals ½ Density * Velocity squared * Area * Drag Coefficient.

Normally this formula is used with the SI-units (kg/m3, m/s, m2). Using the normal units I get ridiculously high numbers, if I use millimeters I get even higher numbers, and adjusting density and drag coefficient just gets me back to what I got with normal units. After some research, I found out that all numbers need to be larger than 1, but when I use millimeters to make the area larger than 1 and adjust all the variables according to that, others become lower (kg/m3 -> g/cm3). Like I said, I suck at math. How should I adjust the units so they’re all above 1 and still give the correct results? Or at least, how do I find out?

Also, if I posted this in the wrong place I apologise. Even if it’s not directly related to Lua, it’s for a Lua script in Garry’s mod, and I figure this should be the place I’ll find people who can answer this question.

Thanks!