An object travels North at # 5 m/s# for #1 s# and then travels South at # 3 m/s# for # 3 s#. What are the object's average speed and velocity?
Travel distance north is
Travel distance south is
Average speed is the total distance travelled divided by total time.
Average velocity is the resultant change in velocity divided by the total time where the final velocity is South;
This scenario may occur in real life when a ping pong ball is returned from a serve.