Skip to content
Dabour HubLEARN · PRACTICE · EXPLORESign inStudent

8.1Physics 02. Light And Sound

Vibration of particles in sound waves why sound needs a medium and… — Cambridge Checkpoint Science 0893 Revision Notes & Topical Questions

5 min read 9 parts Lesson 1 of 5 1 quiz

📚 Cambridge Checkpoint Science 0893 Hub / Topical Revision
🩺
100% Curriculum Specification Match Lesson Doctor Verified
The only platform with 100% curriculum specification match and verified interactive question banks.
0%read
Lesson summary

8.1 Sound waves: vibrations, particles and the need for a medium — CHECKPOINT - Lower Secondary Science 0893 notes: Describe sound as vibration of particles in a sound wave and explain why sound needs a medium and cannot travel in a vacuum.Vibration — things that vibrate, moving …

  • How a wave forms
  • Particle motion
  • Speed in air
  • Energy transfer
  • Quiet sounds
  • Bell jar evidence

Section 1 of 9Source of sound

Vibration
  • Vibration things that vibrate, moving backwards and forwards very quickly, make sounds.
  • A drum, vocal cords, guitar strings and a loudspeaker cone are examples.
Loudness
  • Loudness hitting or plucking harder gives a larger vibration and a louder sound.

Section 2 of 9Sound waves

Sound waves
Sound wave
  • Sound wave the way sound travels from a vibrating object to the ear.
How a wave forms
  • How a wave forms a vibrating object pushes the air particles next to it, and these particles make their neighbours vibrate in turn.
Particle motion
  • Particle motion the particles vibrate backwards and forwards in the same direction in which the wave travels.
Speed in air
  • Speed in air about 343 metres per second.

Section 3 of 9Energy of sound

Energy transfer
  • Energy transfer sound waves transfer sound energy.
Effects
  • Effects very loud sounds can damage ears, and sound at a certain pitch can break a glass.
Quiet sounds
  • Quiet sounds vibrations that are too small cannot be detected by the ear.

Section 4 of 9Medium

Medium
  • Medium the substance a sound wave moves through.
  • Solids, liquids and gases can all be a medium.
Solids
  • Solids sound travels well through solids, such as a table or a taut string.
Liquids
  • Liquids whales and dolphins communicate with sounds under water.

Section 5 of 9Sound in a vacuum

Vacuum
  • Vacuum a space with no particles.
No sound
  • No sound there are no particles to vibrate, so sound cannot travel through a vacuum.
Space
  • Space space is almost a vacuum, so an explosion in space would not be heard.
Bell jar evidence
  • Bell jar evidence an electric bell in a jar is seen vibrating when the air is pumped out, but it can no longer be heard.

Section 6 of 9Needs for hearing a sound

Needs for hearing a sound
A vibration to make the sound.
A medium with particles for the wave to travel through.
A receiver such as an ear.

Section 7 of 9Modelling a sound wave

  • Slinky spring
    • marks on the spring represent particles moving backwards and forwards while the wave travels along it.

Section 8 of 9Key terms

TermMeaning
VibrationRapid backwards and forwards movement.
Sound waveA series of particle vibrations carrying sound energy.
MediumThe material that a wave moves through.
VacuumA space with no particles.
ParticleA tiny portion of matter.

Section 9 of 9Exam technique

1
Sound travels through space — sound needs a medium with particles.
2
Air particles travel from the source to the ear — they only vibrate about their positions.
3
Sound is only heard in air — it also travels in solids and liquids.
4
Louder sounds are faster — loudness depends on the size of the vibration.

Last updated: