Lesson 67 of 84 · Forces
Experiment⭐ 30 XP⚡ Spark LabFriction: The Force That Slows (Part 3)
Friction: The Force That Slows (Part 3).
🎯 Your mission
Set it up. Test it. Be amazed.
⚡ The twist
Energy never disappears — it just hides somewhere else.
Mind = Blown
🎢 You feel weightless on a roller coaster because you and the seat are falling at the same speed.
Make a hypothesis first
Before you start: which will move faster, and why?
What You'll Learn
Friction is a force that opposes motion between surfaces that touch. Rough surfaces create more friction than smooth ones. Without friction, you could not walk or grip objects.
Key Words
- inertia
- momentum
Materials Needed
- toy cars
- ramps
- string
- weights
Safety First
- Handle glass items carefully to avoid breakage.
- Do not mix unknown chemicals together.
Steps
Study the diagram and label the parts you recognize.
Set up a pendulum with string and a washer. Change the string length and count swings per minute for each. Graph your results.
Draw a detailed diagram of what you observe.
Write a conclusion: what did your results show? Did they match your prediction?
Check Your Understanding
Question 1
1 of 3What does friction do?
Where you see this in real life
You use this every time you flip a light switch, ride a bike, or kick a ball.
Stretch Challenge
Try this in real life this week.
Time how long a small ball rolls down something, then change the slope and try again.
For the dinner table
“Show me something at home that uses this kind of energy.”
Next Smart Experiment
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