Transverse & Longditudinal

• Transverse & Longitudinal Waves

  • Waves are repeated vibrations that transfer energy
  • Energy is transferred by parts of the wave knocking nearby parts
  • This is similar to the effect of people knocking into one another in a crowd, or a "Mexican Wave" at football matches
  • Waves can exist as one of two types:
  • Transverse
  • Longitudinal
• Transverse Waves

  • Transverse waves are defined as: Waves where the points along its length vibrate at 90 degrees to the direction of energy transfer
  • For a transverse wave:
  • The energy transfer is perpendicular to wave motion
  • They transfer energy, but not the particles
  • They can move in solids and on the surfaces of liquids but not inside liquids or gases
  • Some transverse waves (electromagnetic) move in solids, liquids and gases and a vacuum
  • The point on the wave that is:
  • The highest above rest position is called the peak, or crest
  • The lowest below the rest position is called the trough
• Examples of transverse waves are:

  • Ripples on the surface of water
  • Vibrations in a guitar string
  • S-waves (a type of seismic wave)
  • Electromagnetic waves (such as radio, light, X-rays etc)
• Longitudinal Waves

  • Longitudinal waves are defined as: Waves where the points along its length vibrate parallel to the direction of energy transfer
  • For a longitudinal wave:
  • The energy transfer is in the same direction as the wave motion
  • They transfer energy, but not the particles of the medium
  • They can move in solids, liquids and gases
  • They can not move in a vacuum (since there are no particles)
  • The key features of a longitudinal wave are where the points are:
  • Close together, called compressions
  • Spaced apart, called rarefactions
• Longitudinal Waves

  A) Rarefraction

  B) Compression

  
• Examples of longitudinal waves are:

  • Sound waves
  • P-waves (a type of seismic wave)
  • Pressure waves caused by repeated movements in a liquid or gas
• Examples of longitudinal waves are:

  • Sound waves
  • P-waves (a type of seismic wave)
  • Pressure waves caused by repeated movements in a liquid or gas
• Wave terms:

  A) Peaks

  B) Compressions

  C) Parallel

  D) electromagnetic waves

  E) vacuum

  F) liquids and solids

  G) gas, liquids

  H) Constant

  I) Changes

  J) constant

  K) Changes

  L) Speed