BSCI 207 Lecture Notes - Lecture 36: Lift-Induced Drag, Parasitic Drag, Drosophila Melanogaster

• School: University of Maryland
• Department: Biological Sciences Program
• Course: BSCI 207
• Professor: Leo Shapiro

Document Summary

Bsci207 - lecture 36 - finish flying and begin swimming. Thrust: force propelling an object in a particular direction (needs to overcome drag force) Drag: force resisting movement of an object through fluid. To maintain velocity, must have enough thrust to match drag (force to decelerate and a force to accelerate) Forces are generated when velocity changes (no force if velocity = 0) Planes get thrust force from engine (fixed wings provide lift) Birds" wings provide both lift and thrust. Wings only produce lift when moving forward through air. This forward movement involves thrust and drag. For larger and faster objects, pressure drag generally far more important than viscous drag. Not so hard to move through fluid. For smaller and slower objects, viscous drag is more important. Swimming microscopic protozoan freezes in place if it stops swimming for a moment. Friction drag provides resistance to shear (in air there"s resistance to shear)