1. Waves Chapter 14 Notes

2. What is a Wave? / A wave is a periodic disturbance of matter (solid, liquid, or gas) / Examples include: / Sound / Light / Ocean waves / A wave is a periodic disturbance of matter (solid, liquid, or gas) / Examples include: / Sound / Light / Ocean waves

3. Wave Energy / Waves are also considered transfers of energy / Energy moves from one point to another while the substance vibrates while staying in place / Waves are also considered transfers of energy / Energy moves from one point to another while the substance vibrates while staying in place

4. Mechanical vs E-M Waves / Mechanical waves need a substance to travel through / Substance is called a medium / Electro-magnetic waves can travel through emptiness (a vacuum) / Mechanical waves need a substance to travel through / Substance is called a medium / Electro-magnetic waves can travel through emptiness (a vacuum)

5. Examples / Name one type of mechanical wave / Name one type of Electromagnetic wave / Name one type of mechanical wave / Name one type of Electromagnetic wave

6. Mechanical Waves / A medium could be a / Solid / Liquid / Gas / In general waves travel fastest through solids and slowest through gases / A medium could be a / Solid / Liquid / Gas / In general waves travel fastest through solids and slowest through gases

7. Waves / As a wave moves from a source the energy spreads out / The waves spread out in concentric spheres / Each sphere forms a wave front / As a wave moves from a source the energy spreads out / The waves spread out in concentric spheres / Each sphere forms a wave front

8. Types of Waves / Transverse Waves / Particles of the medium move perpendicular to the direction of the wave / Longitudinal Waves / Particles of the medium vibrate parallel to the direction of the wave / Transverse Waves / Particles of the medium move perpendicular to the direction of the wave / Longitudinal Waves / Particles of the medium vibrate parallel to the direction of the wave

9. Types of Waves / Transverse / Rope/String / _________ / Longitudinal / Coiled spring / _________ / Transverse / Rope/String / _________ / Longitudinal / Coiled spring / _________

10. Surface Waves / Occur at the boundary of two mediums / A ball floating on water is a great example / Move both perpendicular and parallel and form a circle / Occur at the boundary of two mediums / A ball floating on water is a great example / Move both perpendicular and parallel and form a circle

11. Characteristics of Waves / The relationship that best describes a wave is a sine curve

12. Crest & Trough / Crest - high point / Trough - low point / Crest - high point / Trough - low point

13. Amplitude (A) / Measures the amount of particle vibration / Determines the energy of the wave / Measures the amount of particle vibration / Determines the energy of the wave

14. Amplitude

15. Wavelength ( ) / Length of just ONE wave

16. Nodes / Point on wave where wave passes through origin

17. Period (T) / Period is the length of time for one wave to occur / Abbreviated with a capital T / Measured in seconds / Calculated as: / Total time / Number of waves / Period is the length of time for one wave to occur / Abbreviated with a capital T / Measured in seconds / Calculated as: / Total time / Number of waves

18. Frequency (f) / Frequency of a wave is how often the wave occurs / Measures the rate of vibrations / Abbreviated as a lower case f / Measured in cycles per seconds (Hertz) / Calculated as: / Number of waves / Total time of waves / Frequency of a wave is how often the wave occurs / Measures the rate of vibrations / Abbreviated as a lower case f / Measured in cycles per seconds (Hertz) / Calculated as: / Number of waves / Total time of waves

19. Period & Frequency / You may notice something about the calculations for period and frequency / They are the inverse of each other / So, / f = 1/T / T = 1/f / You may notice something about the calculations for period and frequency / They are the inverse of each other / So, / f = 1/T / T = 1/f

20. Wave Speed / Not all waves travel at the same speed / Speed is determined by two things / The frequency of the vibrations / The medium of the wave / Calculation for wave speed is / Speed = frequency x wavelength / Not all waves travel at the same speed / Speed is determined by two things / The frequency of the vibrations / The medium of the wave / Calculation for wave speed is / Speed = frequency x wavelength

21. Wave Interactions / Interactions include / Reflection / Refraction / Diffraction / Interference / Interactions include / Reflection / Refraction / Diffraction / Interference

22. Reflection / Reflection is the bouncing of a wave off of a surface or boundary / Boundaries can be / Fixed / Free / Reflection is the bouncing of a wave off of a surface or boundary / Boundaries can be / Fixed / Free

23. Refraction / Refraction is the bending of a wave as the wave passes from one medium to another medium

24. Diffraction / Diffraction is the bending of a wave as the wave passes around an obstacle or an edge / Corner of a room / Slit or hole / Diffraction is the bending of a wave as the wave passes around an obstacle or an edge / Corner of a room / Slit or hole

25. Interference / Interference is the combination of two or more waves to form a new wave / Constructive - waves becomes larger / Destructive - waves become smaller / Interference is the combination of two or more waves to form a new wave / Constructive - waves becomes larger / Destructive - waves become smaller

26. Standing Waves / Standing waves form when a wave is reflected off of a boundary / Interference of the original wave interferes with the reflected wave causing the medium to vibrate in a stationary pattern / Creates nodes and anti-nodes / Standing waves form when a wave is reflected off of a boundary / Interference of the original wave interferes with the reflected wave causing the medium to vibrate in a stationary pattern / Creates nodes and anti-nodes