David Drummer, physics teacher at Kutztown Area High School in Kutztown, PA uses a K’NEX® rollercoaster and Vernier 25-g Accelerometer to investigate impulse. His students mount the Accelerometer in a rollercoaster car and roll it down the coaster into a brick barrier. David has his students use the acceleration data and the mass of their car to produce a Force vs. Time graph for the impact. David then challenges his students to design crash protection using paper and masking tape to reduce the maximum force needed to stop the car.

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The graph shown above is one student’s data showing the force for the car without protection along with two trials with different protection. These results really bring home the point that increasing the time for the collision reduces the maximum force imparted on the car.

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K’NEX is a registered Trademark of K’NEX Industries, Inc.