Waves
In GCSE physics curriculum, there are two types of shock waves: P – waves and S – waves. Differences in the speed of P – and S- waves can be used to give evidence for the structure of the Earth.
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Waves are regular patterns of disturbance that transfer ENERGY in the direction the wave travels without transferring matter- there are two types of LONGITUDANAL and TRANSVERSE.
LONGITUDANAL WAVE – Each particle moves backwards and forwards in the same plane as the direction of wave movement. Each particle simply vibrates to and from about its normal position.
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TRANSVERSE WAVE - Each particle moves up and down at right angles (90˚C) to the direction of wave movement. Each particle simply vibrates up and down about its normal position.
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In GCSE physics, the distance travelled by a wave can be worked out using the formula:
Distance (metres) = Wave speed (metres per second m/s) x Time (seconds)
All waves have several important features:
- Amplitude – The maximum disturbance caused by a wave. It is measured by the distance from a crest or trough of the wave to the undisturbed position.
- Wavelength– The distance between corresponding points on two adjacent cycles.
- Frequency – the number of waves produced in one second. Frequency is measured in hertz (Hz).
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Wave speed, frequency and wavelength are related by the following formula mentioned in GCSE physics curriculum:
Wave speed (metres per second, m/s) = Frequency (hertz, Hz) x Wavelength (metres, m)
For a constant wave speed, the wavelength is INVERSELY PROPORTIONAL to the frequency
End of this topic!
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Drafted by Gina (Physics)