chapter 11

• wavefront


  imaginary line that joins all adjacent points on the wave that are in phase, such as crests
• vibration/oscillation

  motion of any selected point in a wave is periodic and repetitive
• waves

  can be transverse or longitudinal

  transverse waves has direction of vibration perpendicular to the direction or wave travel

  longitudinal waves has direction of wave vibration parallel to direction of wave propagation
• displacement

  displacement of any point on the wave is a vector pointing from its rest position to the point
• amplitude

  amplitude of a wave is its maximum magnitude of displacement from its rest position
• crests

  highest point of a transverse wave
• troughs

  lowest point of a transverse wave
• in phase

  describes two points on a wave that always have the same direction of motion

  all troughs are always in phase

  all crests are always in phase
• wavelength

  shortest distance between 2 successive crests or troughs
• waveform


  shape of the wave
• period

  time taken by each point on the wave to complete one oscillation

  si unit is seconds
• frequency

  number of oscillations each point completed per seconds

  si unit is hertz
• wavelength

  shortest distance between two successive points

  si unit is metre
• wave speed


  distance travelled by wave per second

  si unit is metre per second
• things to note

  wave speed is determined by the properties of the medium

  frequency will always be the same as the wave travels from one medium to another