Lesson 67 of 84 · Motion and Forces
Lesson⭐ 30 XP⚡ Spark LabFriction: The Force That Slows (Part 3)
Motion and Forces.
🎯 Your mission
Learn the rule. Then catch nature using it.
⚡ The twist
The opposite of what you expect is often what happens.
Mind = Blown
🎢 You feel weightless on a roller coaster because you and the seat are falling at the same speed.
Make a hypothesis first
Predict: what happens if you double the force?
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
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
We'll pick an experiment that matches exactly how you're thinking right now.
Share this experiment
Send it to a parent who's looking for a 10-minute kitchen science win.
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