How can we model sound waves?

Transcription

1 Guiding Question How can we model sound waves? Activity 2: Making Sound 1

2 Key Vocabulary Key Vocabulary } audiogram } compression } frequency } function } hertz } pattern } rarefaction } sound intensity } structure } wave Activity 2: Making Sound 2

3 Get Started Does a sound, or noise, sound exactly the same to everyone who hears it? } Record your answer in your notebook. Activity 2: Making Sound 3

4 Introduction Read the introduction and look for key ideas Activity 2: Making Sound 4

5 Get Started Frequency Activity 2: Making Sound 5

6 Get Started SEPUP model for collaborative work } Activity 2: Making Sound 6

7 Do the Activity Complete procedure part A } Record your data in your notebook Activity 2: Making Sound 7

8 Do the Activity Complete procedure part B } Record your data in your notebook. Activity 2: Making Sound 8

9 Do the Activity Safety Note } Be sure to handle the springs in a safe manner so as to avoid hurting each other or damaging the springs. Activity 2: Making Sound 9

10 Analysis Analysis 1 } A wave is a disturbance that repeats regularly in space and time and that transmits energy from one place to another with no transfer of matter. Do the sounds discussed in this activity fit the definition of a wave? Explain, using an example from this activity. Yes, the sounds used in this activity fit the definition of a wave. An example is a guitar. It transmits sound as wave energy from the source (the strings) to the receiver (our ears). The guitar has a disturbance that repeats regularly because the strings vibrate back and forth. We can see the source of the sound in the vibrating strings. Activity 2: Making Sound 10

11 Analysis Analysis 2 } Predict what happens to the amount of energy transmitted by a wave } If the FREQUENCY is increased the ENERGY is increased. If the LOUDNESS is increased, the ENERGY is increased. Activity 2: Making Sound 11

12 Analysis Analysis 3 } Sound is known as a pressure wave. Did your model support this claim? Explain how it did or did not. Yes, our spring model supports the idea that sound is a pressure wave. When we pulled the spring back and released it, it applied pressure in the form of a compression on the metal that traveled down the spring. Activity 2: Making Sound 12

13 Analysis Analysis 4 } Make two tables like the one below, and fill in the missing diagrams to show changes in loudness and frequency. Then explain what your diagrams model. Activity 2: Making Sound 13

14 Analysis Analysis 4 continued Activity 2: Making Sound 14

15 Analysis Analysis 4 continued Activity 2: Making Sound 15

16 Analysis Analysis 5 } a: José has decreased hearing in the right ear at higher frequencies. } Audiogram #4 } b: Leon has noticed lately that he has trouble deciphering women s speech. } Audiogram #2 } c: Shannon has moderate hearing loss involving sounds of 3,000 6,000 Hz. } Audiogram #1 } d: Sophia has profound hearing loss in both ears. } Audiogram #3 Activity 2: Making Sound 16

17 Review Key Vocabulary definitions } audiogram - A graph that shows the sensitivity of a person s hearing for various frequencies. } compression - The region of the wave in which the material through which the wave is transmitted is pressed together. For sound, compressions are regions of high pressure. Activity 2: Making Sound 17

18 Review Key Vocabulary definitions } frequency - The number of times an event repeats in a given time. For sound it is the number of vibrations per second. } function - A purpose or function which a particular thing can perform. Activity 2: Making Sound 18

19 Review Key Vocabulary definitions } hertz (Hz) - A unit of measurement for frequency. One hertz is equivalent to one cycle per second. The unit is named after the German physicist Heinrich Hertz ( ). } pattern - Something that happens in a repeated and predictable way. Activity 2: Making Sound 19

20 Review Key Vocabulary definitions } rarefaction - The region of a wave in which the material through which the wave is transmitted is spread apart. For sound, rarefactions are regions of low pressure. Activity 2: Making Sound 20

21 Review Key Vocabulary definitions } sound intensity - A measurement of how much sound energy passes through a certain area in a certain amount of time as it spreads out from the source; measured in watts per square meter (W/ m 2 ). } structure - The way something is formed, built, or organized. Activity 2: Making Sound 21

22 Review Key Vocabulary definitions } wave - A disturbance that repeats regularly in space and time and that transmits energy from one place to another with no transfer of matter. Activity 2: Making Sound 22

23 Extension Extension } What is perfect pitch and how does it relate to the frequency of a sound? Investigate which individuals are more likely to have perfect pitch. Activity 2: Making Sound 23