# Homework Help: Dynamic Stall pressure

1. Sep 17, 2012

### nowayjose

1. The problem statement, all variables and given/known data

$\frac{1}{2}$rho0VEAS^2= $\frac{1}{2}$rhoVTAS^2

3. The attempt at a solution

Basically what i've understood is that the TAS (true air speed) doesn't matter when calculating the stall dynamic pressure since what matters is the speed at which the plane is going relative to its surroundings.

The pitot tube is calibrated such that we can the use the EAS (equivalent airspeed) at any height and account for the relative changes in speed at different altitudes.

What i doent understand is the first part of the equation equates the latter and why rho0 is used. I know that to calculate the stall dynamic pressure at sea level we need to use rho0 and the EAS then... But how that equates any rho for a specific TAS doesn't quite make it into my understanding.