WAVES WAVES a disturbance that transfers energy Carries
![WAVES WAVES](https://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-1.jpg)
WAVES
![WAVES a disturbance that transfers energy Carries energy from one place to another Ø WAVES a disturbance that transfers energy Carries energy from one place to another Ø](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-2.jpg)
WAVES a disturbance that transfers energy Carries energy from one place to another Ø Classified by what they move through Ø 1. 2. Mechanical Waves the energy is transferred by vibrations of medium (medium = matter) ex/ ocean waves move through water Electromagnetic waves (EM Waves) the energy moves through disturbances in the electromagnetic field.
![WAVE STRUCTURE CREST (peak) AMPLITUDE resting to max peak WAVELENGTH TROUGH WAVE STRUCTURE CREST (peak) AMPLITUDE resting to max peak WAVELENGTH TROUGH](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-3.jpg)
WAVE STRUCTURE CREST (peak) AMPLITUDE resting to max peak WAVELENGTH TROUGH
![MECHANICAL WAVES require a medium (the material through which the disturbance is moving) to MECHANICAL WAVES require a medium (the material through which the disturbance is moving) to](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-4.jpg)
MECHANICAL WAVES require a medium (the material through which the disturbance is moving) to transmit energy travel through & gradually lose energy to that medium Ø Examples: l Ø water, sound, rope, & spring waves Mechanical Media: l water, air, rope, spring Making a pulse WATCH THE VIDEO!!! https: //www. youtube. com/watch? v=-k 2 Tu. Jf. NQ 9 s
![MECHANICAL WAVES Classified by how medium vibrates Pulse = direction of energy transfer Vibration MECHANICAL WAVES Classified by how medium vibrates Pulse = direction of energy transfer Vibration](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-5.jpg)
MECHANICAL WAVES Classified by how medium vibrates Pulse = direction of energy transfer Vibration = direction of vibration of medium relative to pulse 3 types: Longitudinal, transverse, surface
![MECHANICAL WAVES Classified by how medium vibrates Longitudinal Waves: Vibration is in the same MECHANICAL WAVES Classified by how medium vibrates Longitudinal Waves: Vibration is in the same](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-6.jpg)
MECHANICAL WAVES Classified by how medium vibrates Longitudinal Waves: Vibration is in the same direction as wave pulse (parallel to wave pulse) Transverse Waves: Vibration is at 900 (right angles) to wave pulse Surface Waves: Vibration is circular Ex/ Ocean waves; surface waves
![TRANVERSE WAVES Vibration is perpendicular to the direction of the motion of the wave TRANVERSE WAVES Vibration is perpendicular to the direction of the motion of the wave](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-7.jpg)
TRANVERSE WAVES Vibration is perpendicular to the direction of the motion of the wave Sideways or up & down Ø Examples: Ø l l S-type earthquake waves Electromagnetic (EM) or light waves
![LONGITUDINAL WAVES Vibration is parallel to the direction of the motion of the wave LONGITUDINAL WAVES Vibration is parallel to the direction of the motion of the wave](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-8.jpg)
LONGITUDINAL WAVES Vibration is parallel to the direction of the motion of the wave Ø Back and forth (compression & rarefraction) Ø Also called compression or pressure wave Ø Examples: l P-type earthquake waves l Sound waves Rarefraction (expansion) Compression
![Waves describe the Earth P waves move through solids & liquids S waves move Waves describe the Earth P waves move through solids & liquids S waves move](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-9.jpg)
Waves describe the Earth P waves move through solids & liquids S waves move through solids only!!! Are these MECHANICAL WAVES? ? YES!! Seismic waves need a medium (the earth!)
![CHARACTERISTICS OF WAVES Waves are described according to their Ø Amplitude measures DISPLACEMENT size CHARACTERISTICS OF WAVES Waves are described according to their Ø Amplitude measures DISPLACEMENT size](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-10.jpg)
CHARACTERISTICS OF WAVES Waves are described according to their Ø Amplitude measures DISPLACEMENT size of the disturbance Ø Wavelength distance of a “repeating unit” Also called a cycle Ø Velocity v speed = how fast wave travels
![AMPLITUDE l l Distance between “rest & crest” or “rest & trough” Gives indication AMPLITUDE l l Distance between “rest & crest” or “rest & trough” Gives indication](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-11.jpg)
AMPLITUDE l l Distance between “rest & crest” or “rest & trough” Gives indication of “power” or “strength” of wave (magnitude of earthquake = Richter scale) l l Does not affect velocity of wave Determines loudness (sound) or brightness (EM wave)
![WAVELENGTH Ø Distance between any two repeating points on a wave crest-crest, trough-trough, expansion-expansion, WAVELENGTH Ø Distance between any two repeating points on a wave crest-crest, trough-trough, expansion-expansion,](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-12.jpg)
WAVELENGTH Ø Distance between any two repeating points on a wave crest-crest, trough-trough, expansion-expansion, compression-compression Ø Determines what colors we see; what notes we hear (pitch) Ø Shorter wavelengths have more cycles per minute because they aren’t as long
![VELOCITY v Ø the rate at which the energy travels; speed & direction Ø VELOCITY v Ø the rate at which the energy travels; speed & direction Ø](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-13.jpg)
VELOCITY v Ø the rate at which the energy travels; speed & direction Ø Depends on medium l l Mechanical waves travel faster through dense mediums EM Waves are faster through less dense mediums
![Frequency ƒ Ø How often number of wavelengths that pass any point per second Frequency ƒ Ø How often number of wavelengths that pass any point per second](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-14.jpg)
Frequency ƒ Ø How often number of wavelengths that pass any point per second Ø measured in wavelengths/second or cycles/second Hertz (Hz) = number of wavelengths in 1 second Ø Frequency is related to velocity: v = ƒ
![PERIOD T Ø How long Amount of time for one wavelength to pass a PERIOD T Ø How long Amount of time for one wavelength to pass a](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-15.jpg)
PERIOD T Ø How long Amount of time for one wavelength to pass a point Ø Related inversely to frequency Period = 1 Frequency 1 = 1 T f
![Internet resources http: //www. glenbrook. k 12. il. us/gbssci/Phys/Class/wavestoc. html To test how well Internet resources http: //www. glenbrook. k 12. il. us/gbssci/Phys/Class/wavestoc. html To test how well](http://slidetodoc.com/presentation_image/c50f5af6b369831c3466f79e4fae05a1/image-16.jpg)
Internet resources http: //www. glenbrook. k 12. il. us/gbssci/Phys/Class/wavestoc. html To test how well you understand go to http: //www. physicsclassroom. com/Class/waves/u 10 l 1 c. cfm#emmech
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