Lesson 13 of 16 · Engineering and Design
Experiment⭐ 30 XP🛠️ Engineer ShopMaterials That Block Sound
Engineering and Design.
🎯 Your mission
Predict it first. Then prove yourself right (or wrong).
⚡ The twist
The first design always fails. That's the point.
Mind = Blown
🛠️ The first computer bug was a literal moth stuck inside a machine in 1947.
Make a hypothesis first
Guess: what's the weakest part of this build?
What You'll Learn
Soft, thick and uneven materials absorb sound energy instead of reflecting it, which is why a carpeted room sounds quieter than a tiled one. Hard flat surfaces bounce sound back and make echoes.
Key Words
Tap a word to see its definition.
Materials Needed
- cardboard box
- phone with sound level app
- speaker
- cloth
- foam
- aluminium foil
Safety First
- Keep the tone quiet — sustained loud sound damages hearing.
Steps
Read the explanation above and note the two key terms before you start.
Play a steady tone into a box and measure the sound level outside it with a phone app. Repeat with the box lined with cloth, then foam, then foil, and rank the four linings.
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 material would absorb the most sound?
Where you see this in real life
Every bridge, building, and gadget you've ever used started with this.
Stretch Challenge
Try this in real life this week.
Find something that's broken at home and try to figure out *why* it broke.
For the dinner table
“What's something around the house you'd redesign — and how?”
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.
Ready?
Materials That Block Sound
Predict it first. Then prove yourself right (or wrong).
Full screen — no distractions
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