Lesson 10 of 12 · Momentum
Experiment⭐ 30 XPSafety Engineering and Momentum
Safety Engineering and Momentum.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
Nature loves to surprise the careful watcher.
Mind = Blown
🔬 The more you look, the more nature shows you.
Make a hypothesis first
Before you start: write down what you think will happen, and why.
What You'll Learn
Seatbelts, helmets, crash barriers and running tracks all apply the same physics: keep the momentum change the same but stretch it over more time and more area. That lowers both peak force and peak pressure on the body.
Key Words
Tap a word to see its definition.
Materials Needed
- bathroom scale or force sensor
- bicycle helmet
- heavy ball
- metre rule
Safety First
- Drop from a low, fixed height with feet well clear.
- Do not reuse a helmet for cycling after impact testing.
Steps
Read the explanation above and note the two key terms before you start.
Drop a melon-sized mass onto a force-sensing scale bare, then through a bicycle helmet's foam. Compare peak readings and calculate the ratio of stopping times implied.
Record what actually happened, including anything that did not match what you expected.
Write a conclusion that answers the question this lesson opened with, and state your uncertainty.
Check Your Understanding
Question 1
1 of 2A helmet's foam liner protects the head by:
Where you see this in real life
This shows up in your everyday life more than you'd think.
Stretch Challenge
Try this in real life this week.
Try one experiment in real life this week — even a tiny one.
For the dinner table
“What's the most surprising thing you learned today?”
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Safety Engineering and Momentum
Run the experiment. Find out what really happens.
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