11-18-2021, 07:04 AM
(11-17-2021, 10:16 PM)Don H Wrote: So I just completed some learning sessions with the crash testing activity as described above. I ended up using an old iPhone 7 to record acceleration. I customised a phyphox test to present a simple graph of just the y axis acceleration as that seem to present the least noisy signal, and more importantly, to display the max/min values. While the abs. maximum measurable acceleration is only ~78 m/s2, most students were able to iterate the design of their crash barriers to achieve acceleration values below this, and thus were able to get a sense of the effect of design changes on barrier performance and compare with their classmates. Hence, I found the app, which seemed to provide reasonably meaningful numeric values despite the limitations of the phone, worked wonderfully for this purpose. In fact, some students well surpassed the performance of my designs with values as low as ~20 m/s2. I look forward to finding or perhaps making other experiments using this app for this age level of students.
Hi Don, thanks for sharing!
Do you have any ideas how to easily measure speed before impact in the same experiment?
Does the car make a detectable sound both when it stops accelerating? I'm thinking of the Acoustic Stopwatch.
I have tried magnets and lights to measure speed but with limited success in the classroom.
Best regards.
//Erik