W.2 Quiz Corrections

What characteristic of sound makes it best modeled as a longitudinal wave?

• The particles in the medium move parallel to the direction of the disturbance
• The particles in the medium move perpendicular to the direction of the disturbance
• Sound is a result of a patterned movement
• Sound energy can be transferred through different materials

Your teacher gently strikes a tuning fork with a hammer. The tuning fork produces a sound wave and the wave is displayed on a computer, as shown in the diagram on the right. Which of the properties of the wave would increase if the teacher hit the same tuning fork very hard with the same hammer?

• Frequency
• Wavelength
• Amplitude
• None of the above

Which of the following observations does not support the claim that sound is characterized by a spectrum of frequencies?

• Older humans are unable to hear the high pitch from some electronics.
• Older humans are unable to hear quieter sounds.
• Several species of animals are able to hear sounds that have frequencies greater than the audible frequency humans are able to hear.
• Dog whistles are designed to release a pitch that is higher than the audible frequency range for humans.

Which of these lengths could represent the wave’s wavelength?

• 1 only
• 1 and 3
• 2 only
• 2 and 4
• 1, 2, 3, and 4

Which of the options below best describes how energy is transported in a sound wave?

• Energy can be transported in a sound wave through empty space, without going through any material.
• Energy cannot be transported in a sound wave.
• Energy is transported in a sound wave by particles that move from sound source to listener.
• Energy is transported in a sound wave by a sequence of collisions between particles in some material.
• Energy can be transported in a sound wave only when the sound is sufficiently loud.

Use the graph shown below to answer the question. A cicada is a tree-dwelling insect that can be found on all continents except for Antarctica. Cicadas are known for their high pitched “songs” that are typically above 17 kHz (or 17,000 Hertz). According to the graph, at what age range do humans stop being able to hear the sounds from cicadas?

• Ages 10-15
• Ages 25-30
• Ages 40-45
• Ages 55-60
• Ages 60-65

Imagine that you were in a soundproofed room with a window, so that you could look into another room right next to it. This second room has a computer that is producing a sound wave. You can’t hear the sound itself, but you can see the computer display through the window of the room, and the sound wave is being represented on the screen. If you saw the wave’s wavelength on the screen increase, what can you say about the sound being produced?

• The sound was higher in pitch
• The sound was lower in pitch
• The sound was louder in volume
• The sound was softer in volume
• None of the above.

The two slinkys represent two different sound waves. Choose the correct statement regarding them.

• Sound A is a higher frequency than Sound B.
• Sound A is a lower frequency than Sound B.
• Sound A is the same frequency as Sound B.

The two slinkys represent two different sound waves. Choose the correct statement regarding them.

• Sound A is a higher amplitude than Sound B.
• Sound A is a lower amplitude than Sound B.
• Sound A is the same amplitude as Sound B.

Consider the two sound waves below and check the correct statement.

• Sound A has a higher pitch than sound B.
• Sound A has a lower pitch than sound B.
• Sound A and Sound B have the same pitch.