Lesson 7 of 12 · Kinematics
Experiment⭐ 30 XPFree Fall and the Value of g
Kinematics.
🎯 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
Near Earth's surface, gravity gives every falling object the same acceleration of about 9.81 m/s², regardless of mass. A hammer and a feather land together in a vacuum; in air they do not, because air resistance acts far more strongly on the feather.
Key Words
Tap a word to see its definition.
Materials Needed
- hardback book
- sheet of paper
Safety First
- Drop from chest height over a clear floor.
Steps
Read the explanation above and note the two key terms before you start.
Drop a sheet of paper and a book side by side and record which lands first. Then place the paper flat on top of the book and drop them together. Explain the change using air resistance rather than weight.
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 2Two objects of different mass fall in a vacuum. They:
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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Free Fall and the Value of g
Set it up. Test it. Be amazed.
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