Physics · KS3 Y7 · Waves (Light & Sound)

Vibrations make sound

Vibrations make soundFree3:10Heddy Score 3 of 7, below the standard
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What you need to know

  • Sound is a longitudinal wave: the air particles vibrate back and forth in the same direction the wave travels.
  • A speaker makes sound by vibrating a cone, which pushes the nearby air back and forth.
  • The vibrations create squashed and stretched regions of air, and these make the eardrum or a microphone vibrate.
  • Higher frequency vibrations are heard as higher pitch; humans hear roughly 20 Hz to 20 000 Hz, and sounds outside that range are ultrasound or infrasound.

In this clip

Runs 3:10, from 1:05 to 4:15 of the full video.

Also coversLight & sound basics
Heddy Score3/7, Below the standard
See the seven stars
  • Trusted source · passed. The creator's own upload, live and playable here.
  • On the map · not judged yet. A teacher watched it: it mainly teaches this map topic.
  • Spec-true · not judged yet. Accurate, and right for the current UK specification.
  • Focused · passed. One idea, short enough to watch in one go.
  • Accessible · passed. Good captions, clear sound and pictures.
  • Safe for children · not judged yet. Right for 11 to 16 year olds, with no sales pitch.
  • Proven · not judged yet. Earned from our students: they learn from it, find it helpful and watch it to the end.
★ passed · ☆ pending · ✕ failed
Our students

Not enough students yet

Our own students' answers. These are what move ★7 Proven.
On YouTube

2.04M views · 20.4K likes · CrashCourse 17.3M subscribers

As reported by YouTube on 2026-11-02. Not part of the Heddy Score.
How the Heddy Score works

Why we picked it

Shows clearly how a vibrating source makes sound and how the ear detects it, with good everyday examples.

CrashCourse on YouTubechecked 2026-10-22

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