When an object of mass \(m_A\) and velocity \(\vec{v}_{Ai}\) undergoes an inelastic collision with a second object of mass \(m_B\) and velocity \(\vec{v}_{Bi}\), we can regard what remains after the collision as a single object of mass \(m_A + m_B\). Momentum conservation then gives us an equation for the velocity \(\vec{v}_f\) of this combined object just after the collision: