Quote:
Originally Posted by ShoeDLG
Going back to sleep eh? ...lazy graduate students...

Okay, I'll respond. Get ready for some sarcasm.
Here is what I learned in 2006:
Work = int( F*dr) from position one to position two. Where * is the dot product, F is the force vector, and dr is the differential position vector. The dot product of two perpendicular vectors is zero.
Here is what I learned in 2007:
Lift is defined as the component of the resultant aerodynamic force perpendicular to the freestream and drag is defined as the component parallel to the freestream. See below.
Combining these two pieces of knowledge gives the following result:
By definition, lift does no work on the object because lift is perpendicular to the direction of motion.