Force and Motion

Answers to Activity Sheet 2

Speed and Acceleration 1

• 1.
  • a) The distance of the race was 100m.
  • b) The runner did not stop at the finish line.
  • c) The runner moved at a constant speed for 10s.
  • d) The runner covered 75m at this constant speed.
  • e) The constant speed was 7.5m/s.
  • f) The average speed for the whole race was 100m/18s = 5.6m/s.

• 2.
  • a) The second runner won the race.
  • b) The average speed of this runner for the whole race was 100m/17s = 5.9m/s.
  • c) The constant speed of this runner was 75m/12s = 6.25m/s.
  • d) The first runner reached the highest speed during the race (7.5m/s).
  • e) The losing runner needs to improve acceleration at the start of the race.

3. [13.1 Insert graph…may be reduced if necessary]