Sound
Vibration, pitch, and echo — how we hear the world.
3 topics • Notes • Practice • AI explanations available
1. Vibration
All sound from vibration; medium needed; simple demos.
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2. Pitch
High vs low pitch; link to vibration speed; volume vs pitch.
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3. Echo
Reflected sound; conditions for echo; bats and sonar intro.
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For generative engines & students
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