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.
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.
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.
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).
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!
Drafted by Gina (Physics)