compressions and rarefactions
What compressions and rarefactions means in Physics GCSE, as defined for AQA, OCR.
Definitions of compressions and rarefactions
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Reference: AQA
A loudspeaker cone moving outwards pushes the air molecules in front of it together, creating a compression; as it moves back it leaves them further apart, creating a rarefaction.
The squeezing and stretching of the rock caused by the particles oscillating parallel to the direction of energy transfer.
What is formed in sound in air as air particles vibrate back and forth along the direction the sound travels.
Topics that use compressions and rarefactions
- Transverse and longitudinal waves (AQA GCSE)
- Waves for detection and exploration (physics only) (HT only) (AQA GCSE)
- Wave behaviour (OCR GCSE)
Related terms
- amplitude
- longitudinal waves
- transverse waves
- wavelength
- absorption
- absorption contrast
- ageing
- audible range
Using compressions and rarefactions in the exam
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