Compressions and rarefactions
What Compressions and rarefactions means in Physics A-Level, as defined for AQA, OCR.
Definitions of Compressions and rarefactions
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Reference: AQA
The regions of high and low particle density in a longitudinal wave, where particles are close together and spread apart.
In a longitudinal wave, compressions are where particles bunch together and rarefactions are where they spread apart.
The formations made by air molecules vibrating parallel to the direction the sound travels.
Topics that use Compressions and rarefactions
- Longitudinal and transverse waves (AQA A-Level)
- Wave motion (OCR A-Level)
Related terms
- Longitudinal wave
- Polarisation
- Transverse wave
- Amplitude
- Classification of waves
- Diffraction and gap-to-wavelength ratio
- Displacement
- Displacement–distance graph
Using Compressions and rarefactions in the exam
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