transverse and longitudinal waves

• Longitudinal waves


  Waves where the vibrations are parallel to the direction of wave travel
• Compression


  An area of increased pressure where the particles are closer together than on average
• Rarefaction


  An area of reduced pressure where the particles are further apart than on average
• Transverse waves


  Waves where the vibrations are at right angles to the direction of wave travel
• Demonstrating longitudinal waves


  Pushing and pulling a stretched slinky spring
• Transverse waves


  • Ripples on the surface of water
  • Vibrations in a guitar string
  • A Mexican wave in a sports stadium
  • Electromagnetic waves - e.g. light waves, microwaves, radio waves
  • Seismic S-waves
• In longitudinal waves, the particles move backwards and forwards between compressions as the wave is transmitted through the medium, but none of the particles are transported along the wave
• Seismic S-waves


  Transverse waves that may be thought of as shake or shear waves as the particles move from side-to-side - crossing the direction of wave travel
• Transverse waves


  • Waves where the vibrations are perpendicular to the direction of wave travel
• Electromagnetic waves are transverse waves with a wide range of properties and uses
• Transverse waves


  • Energy is transferred from left to right, but none of the particles are transported along the wave
  • The particles move up and down as the wave is transmitted through the medium
• Transverse waves are often demonstrated by moving a rope rapidly up and down
• In the diagram, the rope moves up and down, producing peaks and troughs
• Medium


  The material through which a wave can be transmitted (propagated)