Ask an Explainer


The website says a Boeing 747's wing can produce one pound per square inch of lift. If lift is a force, why is it being expressed in pounds(a unit of mass)?


Traditionally, pounds (lbs) are a unit of force as well. There is such thing as pound-mass, but this is a very uncommon and rarely used unit. In the Imperial system, pounds are a unit of force (like Newtons) and slugs are a unit of mass (like kilograms). 

Categories: Forces of Flight