Design a crash barrier

Materials for the egg drop challengeConstruct a crash barrier designed to minimize the impact force experienced by a cart in a collision.

Test equipment: Smart Cart with bumper, dynamics track with feet and end stops.
Barrier materials: straws, popsicle sticks, toothpicks, newspaper, craft paper, bathroom tissue, aluminum foil, duct tape, cotton balls, thread, and cardboard.
Other constraints: maximum impact force is less than 10.0 N, maximum mass is 50 g, maximum length is 12 cm, and the front of the crash barrier is flat.
When a car impacts a wall, the wall exerts a strong force on the car to abruptly change the car’s momentum over a very small time interval. Common features on highways are crash barriers built to reduce the force of incidental impact from cars. Crash barriers reduce the force during a collision by lengthening the time interval over which the impact occurs. Show Alternate expression of Newton’s second law
Test different materials and configurationsSet up your test equipment. Use the DC_CrashBarrier experiment file to record data. Use your test station to test different barrier materials and configurations you might use in your design. Vary one or two parameters: padding material, shape, and so on. Write a testable hypothesis on the effect of each parameter.
Design the crash barrier based on test results. Describe your design with words and sketches.
Construct a prototype of your design. If necessary, update your design to include any changes made during prototyping as a result of unforeseen problems.
Test your prototype. Before running the test, identify what you will be evaluating at the conclusion of each test, such as what parts of the barrier did not perform as expected.
Analyze the tests to determine which design elements produce the best performance relative to the design criteria. What evidence led you to those conclusions? Document the strengths and weaknesses of your prototype in your report.
Based on your evaluation, redesign your barrier using the design elements that best meet the evaluation criteria. Then prototype and test it in preparation for the final evaluation.
Your teacher will evaluate each submitted barrier by measuring its mass and length (less than 50 g and shorter than 12 cm), and launching a cart across a level track (using the cart plunger pressed-in three clicks) into the flat front of the crash barrier. The peak force must not exceed 10.0 N. Afterward, each student group will present to the class a short summary of their design and performance. As a class, discuss what design elements performed best.

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