The juniors in fourth and seventh period Physics are literally “going through the motions” while learning kinematics – but in a good way! They have kicked off this unit on the study of motion with several hands-on activities, including a “Subway Speed Lab” and a “Three-Legged- Race.” After watching a short video showing a real life subway crash, students became aware of the role that speed plays in safety. To practice calculating speed and exploring what factors affect it, students created a balloon and string model of a subway car, which when assembled properly, shoots the balloon across a string like a subway car on rails. The physics students calculated the speed of their “subway” using the formula.
Next came the epic three-legged race! To demonstrate the difference between instantaneous speed and average speed, students were challenged to compete in pairs and finish a 25 meter 3-legged dash. While several students volunteered to compete in the race itself, other students helped record racers’ times with a stopwatch, so that their average speeds could be calculated later, and record the race in slow motion so that the class could watch an “instant replay.” Not only did this prove to be highly entertaining, but it also helped to clarify the difference between the overall speed (average) and the speed at a specific moment in time (instantaneous). This is activity was also a perfect segue into their next lesson on acceleration, which describes changes in speed over time.