Not sure how advanced this q is, Dave, but ANY change in direction of a flow requires the application of a force (F=MxA) - in this case applied by the angle of attack of the aerofoil and its camber - and ANY force has an equal and opposite reaction. This applies whether the air is moving over the wing or the wing moving through the air. This reaction can be resolved into vertical (lift) and horizontal (drag).
Is that what you are after or have I taught grandma to suck those eggs?
