Worksheet answers Describing motion_w.doc - Describing ... Describing motion Worksheet answers Part 1: Simulated 100 m race 1. Describe the runner's motion (acceleration, deceleration, or constant speed) during each phase of the race. drive (0-3 s) acceleration maintenance (4-7 s) constant speed slowing down (8-10 s) deceleration 2. Which of Newton's laws of motion best explains each of the following? a.