Lesson 26 of 84 · Forces
Simulation⭐ 30 XP⚡ Spark LabHow Sound Waves Travel
How Sound Waves Travel.
🎯 Your mission
Push the limits. See what changes.
⚡ 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
Sound is a wave made by vibrations that travel through a material such as air, water, or metal. The vibrations bump particles into one another to carry energy to your ears, which is why sound cannot travel through empty space.
Key Words
Tap a word to see its definition.
Steps
Read about Forces and write down three key facts.
Test friction: pull a weighted box across 4 surfaces (carpet, tile, sandpaper, foil). Use a spring scale to measure the force needed for each.
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 Newton's third law state?
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.”
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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