Unit 18
Academic Physics
Name___________________
Vibrations and Waves
Note: Answers to the questions below may be found in Chapter 25 on page 372 of the conceptual
physics textbooks located in the back of the room. You must read this chapter in order to understand the
material presented in this unit.
1. A “wiggle” in time is known as a ________________________.
2. A “wiggle” in space and time is known as a __________________________.
3. A _____________________ is a simple machine often used in controlling the motion of clocks.
4. The back and forth motion of a pendulum is known as ____________ ____________ ____________.
This motion traces out a special curve known as a ______________ __________________.
5. The high points of a pictorial depiction of a wave are known as ____________________.
6. The low points of a pictorial depiction of a wave are known as ____________________.
7. Amplitude is the distance from the midpoint to the _______________ or the ________________ of
the wave.
8. __________________ is the distance from the top of one crest to the top of the next crest.
Alternatively, the __________________ is the distance between identical parts of the wave.
9. __________________ is how often a vibration occurs. The ________________ of a vibrating object
(weight on a spring, pendulum bob, etc.) specifies the number of back and forth vibrations the object
makes per second.
Answer questions 10-14 based upon the figure to
the right.
A
C
10. Points “A” and “C” are ________________.
11. Point “D” is a _______________________.
12. The distance between points “A” and “B” is
B
known as an __________________________.
D
13. The distance between points “A” and “C” is known as a _____________________.
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Unit 18
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14. How many complete wavelengths are shown in the figure below? ___________________________
A
B
C
15. Draw a line from each of the points above (A, B, and C0 to their corresponding point on the next
wave. The lengths of these lines represent the _____________________ of the associated wave.
16. A wave has a wavelength () of .35 m and a frequency (f) 13.5 s-1. Using the formula found in
Chapter 25, calculate its speed.
17. A wave traveling at 100 m/s is found to have a frequency of 10 vibrations per second. What is the
wavelength of this wave?
18. A wave with a known wavelength of 1.35 m is found to have a velocity of 225 m/s. What is the
frequency of this wave?
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Unit 18
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Vibrations and Waves
Note: Answers to the questions below may be found in Chapter 25 on page 372 of the conceptual
physics textbooks located in the back of the room. You must read this chapter in order to understand the
material presented in this unit.
19. A wave in which the motion of the medium is at right angles to the direction in which the wave
travels is known as a __________________________ wave.
20. A wave in which the particles in the medium move back and forth in the same direction in which the
wave moves is known as a _____________________ wave.
21. The wave pictured below is a _________________________ wave.
22. The wave pictured below is a _________________________ wave.
23. When two or more waves occur in close a proximity to each other, they will produce
___________________ patterns.
24. These patterns may produce ______________________ or destructive _______________________.
25. If two waves interact with each other and produce a wave that has a larger amplitude than the
original waves, then we say that these waves have completely or partially ______________________
each other.
26. If two waves interact with each other producing a wave that has a smaller amplitude than the
original waves, then we say that these waves have completely or partially ______________________
each other.
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Unit 18
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27. Draw a line from the “parent” waves in the left column to their “offspring” found in the column on
the right. Be sure to read the vertical scales on the offspring graphs as the scales are not all the same.
Sum
1.50
1.00
2.50
2.00
0.50
1.50
1.00
0.00
0.50
0.00
-0.50
-0.50
-1.00
-1.00
-1.50
-2.00
-1.50
-2.50
Sum
1.5
1
2.50
2.00
0.5
1.50
1.00
0
0.50
0.00
-0.5
-0.50
-1.00
-1
-1.50
-2.00
-1.5
-2.50
Sum
1.50
1.00
0.50
1.50
1.00
0.50
0.00
0.00
-0.50
-0.50
-1.00
-1.00
-1.50
-1.50
Sum
1.50
1.00
0.50
1.50
1.00
0.50
0.00
0.00
-0.50
-0.50
-1.00
-1.00
-1.50
-1.50
EIMASES © 2001-2009 Mr. Shannon W. Helzer. All rights reserved.
Unit 18
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Sound
Note: Answers to the questions below may be found in Chapter 26 on page 391 of the conceptual
physics textbooks located in the back of the room. You must read this chapter in order to understand the
material presented in this unit.
28. All sounds are produced by the ________________________________ of material objects.
29. Which wave type transfers sound vibrations through the medium known as “air?” Refer to chapter
30 for the two types of waves discussed. __________________________________________________
____________________________________________________________________________________
31. In your own words explain what is meant by the term compression.
____________________________________________________________________________________
____________________________________________________________________________________
____________________________________________________________________________________
32. In your own words explain what is meant by the term rarefaction.
____________________________________________________________________________________
____________________________________________________________________________________
____________________________________________________________________________________
33. In the figure below, label and circle a rarefaction and a compression.
34. Transmission of sound requires a __________________________ which conducts the sound away
from its source.
35. ________________ and ___________________ are also conductors of sound. Indeed, they are
better conductors of sound than is air.
36. __________________________ is a physiological sensation sensed by the brain of an organism.
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Unit 18
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37. Why is the sound of a tuning fork more audible when it is mounted than when it
is free? What is a sounding board? Forced Vibration?
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
38. When two mounted tuning forks are placed in close
proximity to each other and one fork is struck, the
second fork will start to undergo forced vibrations.
What is this phenomenon called?
_____________________________________________
_____________________________________________
39. On the left side of the figure below are two pairs of longitudinal wave patterns. On the right side of
the figure are the resulting interference patterns. Draw a line from the pair on the right to their resulting
interference pattern. Explain why you selected the pattern you picked.
Explain your choice. Label the figures to the right as either constructive or destructive interference:
____________________________________________________________________________________
____________________________________________________________________________________
____________________________________________________________________________________
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Unit 18
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40. When two sound waves of different wavelengths interfere, they produce a rhythmic series of “dead
zones” and “beats.” What is a Beat?
____________________________________________________________________________________
41. The dead zones occur where the waves interfere destructively, and the beats occur where the waves
interfere constructively. The figure below shows two such interfering waves. Circle the positions on
these waves where destructive interference will occur and square the areas of these waves where
constructive interference will occur. One destructive interference zone is circled for you. The actual
interference pattern is shown below.
Interfering waves:
Resulting interference pattern:
The questions below are review questions from Unit 17 Worksheet 82. You must have these correct in
order to get homework credit for this worksheet.
42. A wave in which the motion of the medium is at right angles to the direction in which the wave
travels is known as a __________________________ wave.
43. A wave in which the particles in the medium move back and forth in the same direction in which the
wave moves is known as a _____________________ wave.
44. The wave pictured below is a _________________________ wave.
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Unit 18
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45. The wave pictured below is a _________________________ wave.
46. When two or more waves occur in close a proximity to each other, they will produce
___________________ patterns.
47. These patterns may produce ______________________ or destructive
________________________.
48. If two waves interact with each other and produce a wave that has a larger amplitude than the
original waves, then we say that these waves have completely or partially ______________________
each other.
49. If two waves interact with each other producing a wave that has a smaller amplitude than the
original waves, then we say that these waves have completely or partially ______________________
each other.
EIMASES © 2001-2009 Mr. Shannon W. Helzer. All rights reserved.
Unit 18
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