Waves sub

• Waves transfer energy and information not matter
• E.g. when object goes into water the ripples transfer energy. The wave particles move up and down but ripples travel across surface

  The water particles always return to original position
• Sound waves transfer energy not matter because air particles move backwards and forwards but always return to original position
• Transverse waves

  • Particles vibrate at 90° to direction of energy transfer(direction wave is traveling)
  • It looks like transverse wave moving up and down
  • Examples are: water waves,electromagnetic spectrum waves
• What are vibrations known as

  Oscillations
• Longitudinal waves

  • Particles oscillate in parrarel with direction of energy transfer(move back and forth in same direction of wave)
  • Waves travel though periods of compression and rarefraction
  • Examples are: sound waves,seismic primary waves
• Amplitude is maximum movement of wave from rest position

  
• Wave speed(m/s)= frequency(Hz) x wavelength(m)
• Wave speed = distance ÷ time
• You can measure speed of sound waves in air with 2 microphones connected to computer

  1. Measure distance between 2 microphones
  2. Make a sound
  3. Calculate time taken for sound to travel from first to second microscope
  4. Then use equation to calculate speed of sound

  Speed of sound = distance between microphone ÷ time on computer
• Between different substances waves are absorbed, transmitted,refracted or reflected but it depends on type of wave and its wavelength
• When wave is absorbed energy is transferred
• What is the time it takes for complete wave oscillation

  Period
• What is number of waves that pass a point each second


  Frequency
• What is the wavelength 


  the distance from a point on wave to next point of wave
• What is the wave velocity


  the speed at which a wave travels through a medium(velocity at which wave moves)
• Why do sound waves transfer energy but not matter


  air particles move backwards and forwards but always return to original position
• Between different substances waves are absorbed, transmitted,refracted or rreflected, What does it depend on?


  type of wave and its wavelength
• What waves are seismic primary waves, sound waves?


  Longitudinal waves
• What examples are Water waves and electromagnetic spectrum waves of?


  Transverse