Specific kinetic energy
= Specific kinetic energy
{title2=$K/m=|\mathbf v|^2/2$}
<Kinetic energy> per unit <mass>. For an acceleration field $\mathbf a$, its change along an actual trajectory is $\Delta(|\mathbf v|^2/2)=\int\mathbf a\cdot d\mathbf r$, by the <chain rule>. This differs by a mass factor from the work integral of a physical force.