I don't know much about air resistance but i would like to learn. Basically all i know is that you assume a basic Taylor expansion and then (for some reason unknown to me) you drop out all terms other then the linear and quadratic ones. Both terms in the equation are velocity dependent (intuitively so) with some coefficient with the linear forms of Beta*D or Y*D (this is only for spheres) where Beta and Y are some terms dependent on the medium and D is the diameter of the sphere. Where my questions come in are what happens to the other terms? also what is the difference (like what causes the different drags?) is the linear shape dependent while the quadratic is more abstract and deals with pressure differences caused by the rushing fluid? and do the other terms get used, for example would a cubic air resistance get used when traveling near the speed of sound? (also what causes the cubic air resistance to arise?). plus how are B and C decided for shapes that aren't spheres, like if i wanted to work out a problem dealing with a rocket ship (a cone with a cylinder) how would the equation get adjusted? Finally are the values of Beta and Y shape dependent? or strictly medium dependent and are there such values for something like higher order terms such as a cubic one? any info would be greatly appreciated.