Formula for Aerodynamic Drag

Theorem

The following formula can be used in aerodynamics to calculate an estimate of the drag on a body $B$ passing through a fluid $F$ (usually air):

$D = \dfrac 1 2 k \rho A v^2$

where:

$D$ is the drag on $B$

$A$ is a representative area of cross-section of $B$

$\rho$ is the density of $F$

$v$ is the speed of $B$ through $F$

$k$ is a coefficient which depends on the conditions, and is a function of the Reynolds number.