Lesson 3 of 12 · Momentum
Experiment⭐ 30 XPElastic and Inelastic Collisions
Elastic and Inelastic Collisions.
🎯 Your mission
Set it up. Test it. Be amazed.
⚡ 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
Momentum is conserved in every collision, but kinetic energy is not. In an elastic collision kinetic energy is also conserved; in an inelastic one some becomes heat, sound and deformation. Objects that stick together undergo a perfectly inelastic collision.
Key Words
Tap a word to see its definition.
Materials Needed
- two trolleys
- spring bumper
- adhesive pads
- track
- timing equipment
Safety First
- Keep fingers out of the collision gap and end-stop the track.
Steps
Read the explanation above and note the two key terms before you start.
Collide two trolleys, first with a spring bumper and then with adhesive pads so they stick. Calculate total kinetic energy before and after each, and account for the shortfall in the sticky case.
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 2In an inelastic collision, which quantity is still conserved?
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
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Elastic and Inelastic Collisions
Set it up. Test it. Be amazed.
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