1. Waves
Chapter 14

2. Types of Waves
A wave is a disturbance that carries energy through matter or space.
The medium is the matter through which a wave travels.
Waves that require medium are called mechanical waves.

3. Transverse waves
Transverse waves are waves which the motion of the particles is perpendicular to the motion of the wave.
The top of the wave is called the crest.
The bottom of the wave is called the trough.
The distance between the crest on one wave to the crest on the next is called the wavelength.

4. Longitudinal wave
Longitudinal waves are waves where the particles in the medium vibrate parallel to the direction of the wave motion.
Compressions are the parts of the wave where the medium is compressed.
Rarefactions are parts of the wave where the medium is spread apart.
The distance between compressions is the wavelength.

5. Surface waves Surface waves occur at the boundary between two mediums.
The particles move both perpendicularly and parallel.

6. Wave Properties Transverse waves have the shape of a sine curve.
Highest point of a transverse wave is a crest.
Lowest point of a transverse wave is a trough.
Amplitude is the greatest distance that particles are displaced from their normal resting position.

7. Wave Properties(continued)
Wavelength is the distance from one crest to the crest of the next wave.
Period is the time required for one full wavelength of a wave to pass a certain point.
Frequency of a wave is the number of full wavelengths that pass a point in a given time interval.

8. In which type of a wave does the particles travel perpendicular to the direction of the wave?
longitudinal
transverse
surface
none of the above 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

9. What is the top part of a wave called?
amplitude
compression
crest
trough 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

10. What do we call is the distance between two crest on a transverse wave?
amplitude
frequency
period
wavelength 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

11. Frequency-Period Equation
F=1/T
Frequency is measured in a unit called a hertz.

12. Wave Speed
wave speed=frequency x wavelength
V=f x λ

13. Doppler Effect
The Doppler Effect is the changed in the observed frequency of a wave resulting from the motion of the source or observer.
As the source is approaching the observer, the wavelength decreases and the pitch increases.
As the source is going away from the observer, the wavelength increases and the pitch decreases.

14. Reflection
Reflection is the bouncing back of a wave when it meets a surface or boundary.

15. Diffraction
Diffraction is when a wave bends around an object or opening.

16. Refraction
Refraction is the bending of a wave as it passes from one medium to another medium.

17. A transverse wave…..
Vibrates particles perpendicular to the direction of wave
Vibrates particles parallel to the direction of the wave
Vibrates both parallel and perpendicular to the direction of the wave
Vibrates particles in one direction
I don’t get it. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

18. In the diagram, identify the wave property “A”
Frequency
Amplitude
Wavelength
I don’t know 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

19. Wave Interference
Wave interference is when several waves are in the same location and the waves combine to produce a single, new wave that is different from the original waves.

20. Constructive Interference
The result of two individual waves coming together to produce a wave of greater amplitude is called constructive interference.

21. Destructive Interference
The result of two individual waves coming together to produce a wave of lesser amplitude than the larger of the original waves is called destructive interference.

22. Interference
As two wave sources combine, the waves pattern changes.

23. Beats Interference of sound waves produces beats.
The beat frequency refers to the rate at which the volume is heard to be oscillating from high to low volume.

24. Standing Waves
Standing wave is when the interference of the original wave with the reflected wave causes the medium to vibrate in a stationary pattern.

25. Standing Wave
Nodes are the areas of a standing wave where there are no vibrations.
Antinodes are areas of a standing wave where there is maximum vibration.

26. Longitudinal Wave

27. Transverse

28. Water Wave

29. Rayleigh Surface Wave

30. Review Questions Name the three types of waves.
transverse, longitudinal & surface
Which type of wave has the particles moving perpendicular to the motion of the wave?
transverse
Which type of wave has the particles moving parallel to the motion of the wave?
longitudinal

31. Review Questions
Which three things can a wave do when it meets a barrier?
reflect, diffract or refract
When the crest from one wave meets the crest of another wave, what happens?
constructive interference
What do you call the top of a transverse wave?
crest

32. Review Questions
On a longitudinal wave, what do you call the part of the wave that is spread out?
rarefaction
What is it called when the sound approaching you gets louder and fades as it is going away from you?
Doppler Effect

33. Review Questions
What happens when the crest of one wave meets the trough of another wave?
destructive interference
What type of interaction occurs when a wave strikes a barrier and bounces back?
reflection

34. Review Questions
What is the relationship between wave speed, frequency & wavelength?
Wave speed=frequency x wavelength
What do we call the interference of waves of slightly different frequencies traveling in the same direction?
beat

35. Review Questions What is the bottom part of a transverse wave called?
trough
What is the part of the longitudinal wave where the wave is pressed closely together?
compressions
What is the interaction of a wave called where the wave changes speed as it passes from one medium to another and bends?
refraction

36. Review Questions
What is the distance between two crests on a transverse wave called?
wavelength
What is the distance between a crest and the resting position called?
amplitude
What do we call the number of waves that pass a given point in a given amount of time?
frequency

37. Review Questions
What do we call the time it takes for one wave to move past a given point?
period
What happens to the frequency of a wave as the wavelength gets longer?
lowers
In which metric units do we measure frequency?
hertz

38. Review Questions What is the material called that waves move through?
medium
What type of wave needs a medium to move?
mechanical
What do we call a disturbance that transfers energy?
wave

39. Review Questions What type of wave is light? transverse
What type of wave is sound?
longitudinal
What type of wave is produced when a wave is interfered with by its reflected wave?
Standing wave

40. Review Questions
What is the part of a standing wave called where there are no vibrations?
nodes
How does the medium affect the wave speed?
the closer the particles, the faster the wave speed
Where do surface waves occur?
boundary between two mediums

41. Internet Cites