Performance Task – Momentum and Change in Momentum
Performance Expectations:
● Apply scientific and engineering ideas to design, evaluate, and refine a device that minimizes
the force on a macroscopic object during a collision.
● Use Force-time data to determine the relationship between them during a collision
GOALS: Your group is a team working for a car company, tasked with designing a bumper system to
minimize the maximum impact force on the car during a collision. This bumper protects the vehicle
occupants by distributing the force over impact time, see change in momentum. All need to complete
these goals:
● Determine the maximum force during impact with and without your bumper.
● Improve upon your bumper design so as to reduce the maximum force.
● Describe the relationship between the maximum force and impact time and the role change in
momentum has in car crashes and safety
GROUPS: You will complete this task with a group selected by your teacher. Although you will work
together to plan, execute, and analyze your project, all written assignments must be completed
individually. You may collaborate before writing, but when writing the final product, you must adhere to
the five-foot rule. (When actually writing up your report, you should be at least five feet away from your
group-mates.) Any reports that have more than 20% similarity do not receive a passing grade.
ROLES: (If your group has less than 4 members, then members will need to perform multiple roles.)
● Data scientist: Operate Labquest and/or logger pro to collect data.
● Recorder: Record all data in an organized format.
● Experimental Manager: Maintains the equipment and leads the experiments.
● Supervisor: Ensures everything runs smoothly and tasks are completed.
BUMPER DESIGN PARAMETERS: Your bumpers must be:
● The design of your group.
● Made of common household materials.
● Designed such that it does not drag on the ramp.
● Can be constructed in the allotted time.
● Must be a practical design for a car bumper.
● Designed such that it can be installed and removed in less than one minute.
MATERIALS: You may make use of any of the following materials.
Provided by Teacher
Possible Household Materials Provided By Students
●
Cart
●
Cardboard (cereal box, egg cartons)
●
Track
●
Foam (packing supplies)
●
Meter stick
●
Springs (from pens, toys, etc)
●
Vernier Force Sensor
●
Rubber Bands, Duct Tape
●
LabQuest
●
Pre-approved materials not listed above
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REQUIRED PROJECT ELEMENTS:
● Project Proposal – Based on what we’ve covered, you must devise an experimental procedure
that will accomplish the goals listed above. In order to complete your proposal provide:
▪ Plan what data you will take and how you will take it. Give a specific description. Your
explanation should include words, equations, and graphs as needed.
▪ Brainstorm design sketches of a bumper design.
o Household materials your group will bring to make your bumper
o Each person is to submit their own design sketch
▪ Justification: Explain why car bumpers matter by answering the following questions.
o Why is it important for a car company to conduct these tests?
o What makes a better car bumper?
o What does force, time, mass and impulse have to do with protecting cars and
people in car crashes?
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Decision Matrix - Decide which of your groups brainstorm sketches is the best by using the
Decision Matrix. Using a minimum of 3 design sketches rate each design. The highest scored
design is the one you will build. Once you’ve made your decision begin your detailed drawing of
your original design.
Test Design 1 – You will create your first bumper design based on your knowledge of force,
Impulse, change in momentum, and materials to minimize the force exerted on your car and
determine the total change in momentum and maximum force exerted.
Redesign – After determining maximum force exerted on your bumper and Impact time and
comparing your design to that of other teams, you will design a second, improved bumper.
NOTE: This is the design only, no testing will be done.
Data Submission – After design test days, your team will be required to submit your results
(maximum force, impact time) via google spreadsheets. This data will be pooled so that all groups
can use it during data analysis.
Recommendations to Car Company - Explain why bumper design matters by explaining the
concepts of force and impulse in protecting people and vehicles during car crashes. Also, analyze
your test results using physics terms and numbers. And finally include a photo of the design of
the redesign of your bumper.
Project Element
Due Date TBA
Points
Proposal (individual)
● Plan
● Brainstorm
15
Decision Matrix (1 per group)
15
Test Design 1 (1 per group)
● Detailed Design
● Photo of Bumper
● Data Collection
● Group Interviews
● Reflection of findings
30
Redesign (individual)
● Photo of redesign
● Explanation of improvements
20
2
Recommendation to Car Company
(individual)
Total Points
20
100
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