First moment of area, abbreviated as Q, also called first moment of inertia, (English mass unit \(\large{\frac{lbm}{ft^2-sec} }\), Metric mass unit \(\large{\frac{kg}{m^2} }\)), is the measurement of a shape's area cross-section relative to an axis, located in space. In practical terms and of relavance to this site, the shape is generally a beam or piece of pipe. It is the resistance of an object to bend around a certain axis. It can be used to determine the location of the centroid, which is the point where the sum of all moments of inertia are equal.
