Video Review
Key Concept Summary
TA Summary
Vocabulary
A wave where the medium is displaced parallel to the direction the wave travels.
The maximum distance that a particle moves from its resting position when a traveling wave passes through it.
The rate that a single wave peak travels in a medium.
A wave's ability to bend around corners and spread behind holes.
A place in a medium where a molecule naturally resides.
The change in speed and direction as a wave moves from one medium into another.
The result of confined waves interfering in such a way that destructive and constructive interference always occur in a fixed location.
Occurs when two or more waves travel through the same medium at the same time.
The distance between successive similar parts in repeating waves.
The act of bouncing off the boundary between two different mediums.
A fixed position of destructive interference in a standing wave.
Wave where the forces stretch the bonds between molecules in a direction that is perpendicular to the direction the wave travels.
The number of wave crests passing a particular point every second.
A fixed position of constructive interference in a standing wave.
True/False
Compression waves travel through all different states of matter.
Musical instruments use standing waves to produce sound.
Waves cause the medium they travel through to change from its equilibrium shape.
Doppler shift measures the absolute speed of the sender.
The major determinants in wave speed are the wave's frequency and amplitude.
Standing waves occur any time two waves interfere with each other.
Analysis
Which of the following is an example of refraction?
Which of the following is a shear wave? (Select all correct responses.)
What necessarily decreases if you increase the wavelength of a sound wave?
What happens to the sound emitted from a radio as it gets further away from you?
Locations in an auditorium where sound becomes soft or muffled could be places of
If you double the frequency of a sound wave,
The amplitude of a sound wave is a physical quantity that determines the
If the spectrum of a star is studied, and the frequencies are shifted towards the blue, what can you conclude about that star?
If the frequency of a sound wave doubles:
When you compare the frequency of a stationary ambulance siren to the frequency you hear when the same ambulance is moving away from you,
Most stringed instruments are designed to produce a pitch determined by the standing wave with one anti-node. On a banjo, however, it is common to pick the string so that it produces a standing wave with two anti-nodes. How do the pitches of the one and two anti-node notes compare?
As the tension in a guitar string is decreased, what happens to the fundamental wavelength?
A violin is in tune with a piano. The piano and violin play an A (440 Hz) at the same time. The violinist fingers the string, shortening it slightly, and hears a beat frequency of 5Hz, telling him that the frequency he is playing differs from the piano by 5 Hz. What frequency is the violinist playing?
In brass and woodwind instruments, the wavelength of the sound wave is determined by the length of the tube that makes up the instrument. With most instruments, you change the length of the tube by opening and closing valves. But with a trombone, you physically move the slide, changing the length of the tube. If a trombone player moves the slide out (lengthening the tube), what happens to the frequency he is playing?
When you inhale helium, your voice is very high pitched. What does this tell you about helium?
Loudness (decibel level) is related to:
In the picture below, a series of ripples are produced by a moving source. What direction is it moving? 
If you hold down a key on the piano without striking it so that it sounds, then strike and release the key one octave higher, you will continue to hear the higher note on the lower key you are holding down. What will happen if you hold down the higher note key and strike and release the lower note and why?
If the amplitude of a water wave gets larger:
Which of the following is a compression wave?
Which of the following properties of a wave is determined by the characteristics of the medium through which the wave travels?
The frequency of a wave is defined as:
In a transverse wave:
Why does a pen placed in a beaker of water appear bent?
When two speakers vibrating at the same frequency are placed in a room, there are places where the sound is very faint. This is an example of:
When someone can be heard talking in another room through an open door, this is an example of:
When light from the hall can be seen in dark room through an open door, this is an example of:
An echo is an example of
How does a standing wave differ from a traveling wave?
Free Response
- What is a mechanical wave?
- How do glass lenses prevent refraction from reversing itself when leaving the glass?
- Why don’t shear waves travel through liquids?
- Explain how reflection of waves in a standing wave might create constructive and destructive interference.
- Why doesn’t changing frequency and wavelength affect wave speed?
- What conditions need to be met in order to produce a standing wave?
- If someone is standing around a corner, why can you hear them talking? Why can’t you see them?
- What is the difference between diffraction and refraction? Give and explain an example of each.
- How do panels and curtains in an auditorium minimize wave interference?
- Why do waves travel through dense material faster than materials that are not as dense?
- Tools like ultrasound, sonar, and seismology give us information about things we cannot see or touch. What properties of waves allow this?
- Instructions for installing stereo speakers specify that they should be placed a certain distance away from walls or other hard surfaces. Why would this be important?
- Mechanical waves move energy from one place to another, as do the heat transfer processes of radiation, convection, and conduction. Compare and contrast how these three phenomena move energy through a medium. Can you think of any other ways that energy can be moved through materials?
- A magnifying lens uses refraction to make objects appear larger. Light also refracts when passing through a plate glass window as well, yet images seen through windows do not normally appear larger. Why?
- Would sound travel at the same speed through gases made of lighter particles as it would through gases made of heavier particles? Justify your answer using Newton’s Second Law of Motion.
- You can make your voice sound higher by inhaling helium. Why do you suppose this is the case? (Hint: The wavelength of sound is fixed by the size of your throat and vocal chords, but the speed of sound through helium is faster than it is through air.)