waves

• A transverse wave moves perpendicular to the direction in which the particles are vibrating (a water wave moves forward but the particles move up and down).
• transverse waves

  A) direction of particle vibrations

  B) direction of wave motion

  
• A sound wave is an example of a longitudinal wave.
• All electromagnetic radiation are transverse waves
• Longitudinal waves moves parallel to the direction in which the particles are vibrating (a sound wave moves forwards and the particles vibrate forwards and backwards).
• longitudanal waves

  A) direction of particle vibrations

  B) direction of wave motion

  
• Long wavelengths diffract more

  
• Short wavelengths diffract less:

  
• Refraction is the change in speed of a wave as it enters a new medium.
• For a wave entering a more dense medium:

  • Speed decrease
  • Wavelength decreases
  • Angle of refraction is less than angle of incidence when angle of incidence is greater than 0o
• For a wave entering a less dense medium:

  • Speed increases
  • Wavelength increases
  • Angle of refraction is greater than angle of incidence when angle of incidence is greater than 0o
• refraction

  A) normal

  B) incidence

  C) refraction

  
• wave anatomy

  A) amplitude

  B) wavelength λ

  C) crest

  D) trough

  
• Period, T - Time taken for one full wave to pass a point. Measured in seconds
• Frequency, f - Number of waves passing a fixed point every second. Measured in hertz (Hz)