Lesson 2 of 6 · Forces and Motion
Experiment⭐ 30 XP⚡ Spark LabFriction Opposes Motion
Forces and Motion.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ 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
Tap a word to see its definition.
Materials Needed
- weights
- spring scale
Safety First
- Have an adult check your set-up before you start, and tidy everything away afterwards.
Steps
Look at the vocabulary words and write a definition for each in your own words.
Test friction: pull a weighted box across 4 surfaces (carpet, tile, sandpaper, foil). Use a spring scale to measure the force needed for each.
Use your senses (except taste) to describe what you notice.
Write a summary of your findings in 3-5 sentences.
Check Your Understanding
Question 1
1 of 3What does friction do?
Where you see this in real life
This is why airplanes can fly and why rockets reach space.
Stretch Challenge
Try this in real life this week.
This week, find one thing in your house that turns one kind of energy into another.
For the dinner table
“Show me something at home that uses this kind of energy.”
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Friction Opposes Motion
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