Drag (physics)

In fluid dynamics, drag (sometimes called fluid resistance) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid.[1] This can exist between two fluid layers (or surfaces) or between a fluid and a solid surface.

Unlike other resistive forces, such as dry friction, which are nearly independent of velocity, the drag force depends on velocity.[2][3] Drag force is proportional to the velocity for low-speed flow and the squared velocity for high speed flow, where the distinction between low and high speed is measured by the Reynolds number.

Drag forces always tend to decrease fluid velocity relative to the solid object in the fluid's path.


Share this article:

This article uses material from the Wikipedia article Drag (physics), and is written by contributors. Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.