Drag

Drag

Drag

Drag- the action of pulling something forcefully or with difficulty

I believe that most of us are familiar with this term, but not in a scientific or engineering respect. Drag is simply a term that is used to describe a force that acts in an apposing direction to motion. So does this mean it is the same as friction? Not technically, because drag is typically used when discussing aerodynamics.

In these terms drag is referring to the amount resistance that the traveling object incurs when traveling through the air. I am sure everyone, at some point has put his or her hand out the window of car while driving. What happens? When you tilt your hand upward, the force of the air moving over your hand pulls it upward. However, once you tilt your hand steep enough it begins to force your arm backward, this is drag in action.

Flow Graphic

Visualization of air moving over an aerodynamic element aka wing ( wing as in the kind used by airplanes not the delicious snack often eaten at sporting events)

In the case of airplanes, racecars or any object for that matter, this force of drag is multiplied the faster the plane or object is moving. Or if math is more your style: drag force= drag coefficient (recall friction coefficient), times the velocity squared. This is an important relationship to understand because most aerodynamic design focuses on how to minimize drag whilst still generating lift or down force, depending if you’re designing a fighter jet or a racecar.

-Mike

hope this article wasn`t a drag ( yeah I know its dry)