Lesson 6 of 12 · Kinematics
Experiment⭐ 30 XPThe Equations of Motion
Kinematics.
🎯 Your mission
Predict it first. Then prove yourself right (or wrong).
⚡ 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
For constant acceleration, four equations link displacement, initial and final velocity, acceleration and time. The most used are v = u + at and s = ut + ½at². Pick the equation that contains the three quantities you know and the one you want.
Key Words
Tap a word to see its definition.
Materials Needed
- ball
- tape measure
- phone with slow-motion video
Safety First
- Drop from shoulder height only, and keep feet clear of the landing spot.
Steps
Read the explanation above and note the two key terms before you start.
Drop a ball from a measured height and time the fall with a phone's slow-motion camera. Use s = ut + ½at² with u = 0 to calculate g from your measurement, then compare your value with 9.81 m/s² and account for the difference.
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 2Which equation would you use to find final velocity from u, a and t?
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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The Equations of Motion
Predict it first. Then prove yourself right (or wrong).
Full screen — no distractions
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