6.1 - Waves in air, fluids and solids

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Created by
Jamie

Cards (18)

  • Waves may be either transverse (light) or longitudinal (sound)
  • The ripples on a water surface are another example of a transverse wave
  • Longitudinal waves show areas of compression and rarefaction such as sound waves travelling through the air. The oscillations in longitudinal waves are parallel to the direction in which the waves transfer energy.
  • A wave is a transfer of energy, they do not transfer matter (i.e. particles)
  • Frequency is the number of waves passing a point each second. It's units are Hertz (Hz)
  • The amplitude of a wave is the maximum displacement of a point on a wave away from its undisturbed position.
  • The wavelength of a wave is the distance from a point on one wave to the equivalent point on the adjacent wave.
  • Waves can be reflected at the boundary between two different materials.
  • Waves can be absorbed or transmitted at the boundary between two different materials.
  • In sound, the amplitude of a wave represents the volume, more energy is transferred the louder a person speaks
  • Sound waves can travel through solids causing vibrations in the solid
  • Within the ear, sound waves cause the ear drum and other parts to vibrate which causes the sensation of sound
  • The conversion of sound waves to vibrations of solids works over a limited frequency range. This restricts the limits of human hearing
  • Frequencies above 20,000Hz are known as ultrasounds because humans cannot detect them with their ears. Humans can only hear frequencies from 20Hz to 20,000Hz
  • Uses of ultrasounds include:
    • Medical scanning and imaging
    • Industrial imaging
  • Seismic waves are shock waves that travel through the earth and across its surface as a result of an earthquake
  • P-waves are longitudinal seismic waves whilst S-waves are transverse seismic waves. S-waves cannot travel through liquids. Both S & P-waves provide evidence for the structure and size of the Earth's core.
  • Echo sounding, using high frequency sound waves is used to detect objects in deep water and measure water depth