Professional Application

Two piloted satellites approach one another at a relative speed of 0.250 m/s, intending to dock. The first has a mass of $4 . \text{00} \times \text{10}^{3} \text{ kg}$, and the second a mass of $7 . \text{50} \times \text{10}^{3} \text{ kg}$. If the two satellites collide elastically rather than dock, what is their final relative velocity?