Dynamic Pressure (indicated with q, or Q, and sometimes called velocity pressure) is the quantity defined by: $q = 1/2 * \rho v^{2}$, where (using SI units), $q$ is dynamic pressure in $pascals$, $\rho$ is fluid density in $kg/m^{3}$ (for example, density of air) and $v $ is fluid velocity in $m/s$.