Lesson 5 of 6 · Sound
Experiment⭐ 30 XPThe Human Ear and Hearing Range
The Human Ear and Hearing Range.
🎯 Your mission
Set it up. Test it. Be amazed.
⚡ The twist
Nature loves to surprise the careful watcher.
Mind = Blown
🔬 The more you look, the more nature shows you.
Make a hypothesis first
Before you start: write down what you think will happen, and why.
What You'll Learn
The pinna funnels sound to the eardrum, which vibrates. Three small bones amplify that motion into the cochlea, where hair cells convert it into nerve impulses. A healthy young person hears roughly 20 Hz to 20 kHz, and the upper limit falls with age and noise exposure.
Key Words
Tap a word to see its definition.
Materials Needed
- tone generator app
- headphones
- quiet room
Safety First
- Start at the lowest volume and raise it only slightly — testing at high volume can damage hearing.
Steps
Read the explanation above and note the two key terms before you start.
Using a tone generator at low volume, find the highest frequency each member of your group can hear. Plot the upper limit against age and describe the trend.
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 structure converts vibrations into nerve signals?
Where you see this in real life
This shows up in your everyday life more than you'd think.
Stretch Challenge
Try this in real life this week.
Try one experiment in real life this week — even a tiny one.
For the dinner table
“What's the most surprising thing you learned today?”
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?
The Human Ear and Hearing Range
Set it up. Test it. Be amazed.
Full screen — no distractions
Checkout complete lesson on Sound for 9th Grade
Get the full Sound track as a printable PDF — all lessons, worksheets, and answer keys.