1. Setup Demo  A, B, and C start out together (same x)  Relative to Earth  A goes 3 units each 10s  B goes 1 units each 10s  C stays at rest  Record the relative positions in the table below. Include signs!

2. Position DATA  Where is each person relative to you? Position of APosition of BPosition of C Relative to B Relative to C t=0 t=10s t=20s t=30s

3. Relative Velocity Velocity of AVelocity of BVelocity of C Relative to B Relative to C v AC =v BC = v AB =v BB =v CB =  From the measured relative position as a function of time,  find the relative velocities in the table below:

4. Patterns  Check your relative velocity answers to see if they fit the expected patterns: a) v BB =0  No one moves relative to themselves  Does this match your answers? b) v CB = -v BC  If you move East relative to the cows, the cows move West relative to you  Does this match your answers ? c) v AC = v AB + v BC  Vector addition of velocities  Does this match your answers?