yr9 - waves introduction

Download Yr9 - waves introduction

Post on 17-Aug-2015




0 download

Embed Size (px)


  1. 1. Dr Pusey www.puseyscience.com
  2. 2. Waves are periodic oscillations that transfer energy from one point to another. The oscillations are disturbances or deviations from the normal location in matter We generally think of this when we think of waves:
  3. 3. Transverse Wave oscillation is perpendicular (up & down) to wave velocity direction. Longitudinal Wave oscillation is in the same direction (along the wave) to wave velocity direction
  4. 4. Wave Motion Heinemann Physics 3A/3B pg 186 - 187
  5. 5. Transverse VS Longitudinal http://www.acs.psu.edu/drussell/Demos/waves/wavemotion.html TRANSVERSE: Particles oscillate perpendicular to wave motion (up and down): LONGITUDINAL: Particles oscillate parallel to wave motion (back and forth)
  6. 6. Fun Facts Strings, Ocean Waves, Sound, etc The frequency of mechanical waves determines if we can hear them or not (audible spectrum). In fluids (air and water), sound waves are almost exclusively longitudinal. A vibrating guitar string is a transverse wave Sound travels from the guitar string to your ear in a longitudinal wave
  7. 7. Fill in the blanks: Listening to mad tunes on Triple J: Sick Tunes Radio Station Radio Listener Longitudinal Transverse Longitudinal
  8. 8. Fun Facts - Electromagnetic Waves Light, Radio Waves, X-rays, all oscillations of the electromagnetic field. The frequency of electromagnetic waves determines if we can see them or not. (visible spectrum) You will learn more about light waves in particular in year 12
  9. 9. Term Definition SI units Frequency ( f ) Number of fluctuations/ oscillations/cycles per second Hz or s-1 Wavelength ( ) The distance between each successive wave m Period ( T ) The time between each successive wave s Amplitude ( A ) The deviation from the mean, of whatever is being studied. (e.g. displacement, pressure, etc) Whatever the units of what is changing over time (e.g. m, Pa, etc)
  10. 10. Ocean wave as measured by eye This is a measurement of Amplitude VS Distance wavelength Amplitude Crest Trough
  11. 11. Pictures of Waves Both Transverse and Longitudinal waves are represented the same way on a graph. Heinemann Physics 3A/3B pg 189
  12. 12. Your Turn What is the amplitude and wavelength of this wave?
  13. 13. Your Turn What is the amplitude and wavelength of this wave? Amplitude = 4 cm Wavelength = 20 cm A