2. When is an overtone harmonic? a. never c. when it is an integer multiple of the fundamental frequency b. always d.

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1 PHYSICS LAPP RESONANCE, MUSIC, AND MUSICAL INSTRUMENTS REVIEW I will not be providing equations or any other information, but you can prepare a 3 x 5 card with equations and constants to be used on the test. It must be hand-written and you may only use one side of the card. There can be no drawings, worked out problems, or instructions for doing problems. If you want to use such a card, it must be turned into me by the end of the day on Monday, November 3. This study guide will be a good preparation for taking the test. By the time you take the test, you should be able to answer all these questions and ones like it using only your card. 1. Waves generated at A are reflected at B to produce a A standing wave as shown in the diagram to the right. What is the number of antinodes present? a. 3 b. 5 c. 6 d. 7 e. 12 B 2. When is an overtone harmonic? a. never c. when it is an integer multiple of the fundamental frequency b. always d. none of the above 3. The word equal in equal tempered scales means that: a. Each note is the same number of Hertz higher than the previous note. b. Each note is the same frequency ratio greater than the previous note. c. Each octave in the scale has the same frequency range. d. Each note is qualitatively equal to all other notes that it is separated from by an integer number of octaves. 4. A major advantage of an equal tempered scale over other types of scales is that a. All the major consonant intervals are perfectly tuned. e. a and b b. Music can be easily transposed. f. a and c c. flats or sharps can be added to correct interval dissonance g. b and c d. a, b, and c 5. As intervals become more consonant, the ratio of the frequencies in the interval: a. becomes smaller c. is made up of smaller integers b. becomes more complex d. is made up of larger integers 6. Although two different musical instruments can produce the same fundamental frequency, the two will still sound different. Which term describes this difference in the quality of the sound from each musical instrument? a. beats b. critical bands c. dissonance d. timbre 7. If on the 12-tone Equal Tempered Scale you defined a special C to be 300 Hz, what would be the frequency of an A? a. 400 Hz b. 450 Hz c. 505 Hz d. 535 Hz 8. If on the 12-tone Equal Tempered Scale you defined a special C to be 300 Hz, what would be the frequency of an E? a. 337 Hz b. 350 Hz c. 378 Hz d. 400 Hz 9. A particular note is 220 Hz. What is the frequency of a note two octaves above it? a. 440 Hz b. 660 Hz c. 880 Hz d. 1,320 Hz 10. Referring to the same note (220 Hz), what note is exactly a fifth above it? a. 264 Hz b. 330 Hz c. 440 Hz d. 1,100 Hz

2 The next three questions refer to the diagram below. The diagram is of a 3.0 m long string with a standing wave pattern as shown. The speed of the waves is 100 m/s. 11. What harmonic is shown? a. 1st b. 2nd c. 3rd d. 4th e. 5th 12. What is the frequency of vibration? a. 11 Hz b. 17 Hz c. 22 Hz d. 33 Hz e. 50 Hz 13. What is the lowest possible frequency of vibration for standing waves on this string? a. 11 Hz b. 17 Hz c. 22 Hz d. 33 Hz e. 50 Hz 14. If you double the tension in a violin string, how will the fundamental frequency of that string change? 15. If two guitar strings are the same length and have the same tension, but have linear mass densities that are in a ratio of two to one, how much higher in frequency will the string with the smaller linear mass density be? 16. If two guitar strings have the same tension and linear mass densities, but one is half the length of the other, how much higher in frequency will the shorter string be? The next two questions refer to the diagram to the right. The diagram is of a tube closed at one end and open at the other. The length of the tube is 1.2 meters. The speed of sound is 343 m/s. The diagram shows a standing wave present in the tube. 17. What harmonic is shown? a. 1st b. 2nd c. 3rd d. 4th e. 5th 18. What is the frequency of the fifth harmonic of the tube (ignore end effect)? a. 214 Hz b. 229 Hz c. 286 Hz d. 357 Hz 19. Two pipes are the same length. One is closed and the other is open. If the fundamental frequency of the open pipe is 300 Hz, what is the fundamental frequency of the closed pipe? a. 150 Hz b. 300 Hz c. 450 Hz d. 600 Hz 20. Carefully cutting off the bottom of a closed pipe so that its length doesn t change will: a. lower the fundamental frequency by an octave and remove the even harmonics b. lower the fundamental frequency by an octave and restore the even harmonics c. raise the fundamental frequency by an octave and remove the even harmonics d. raise the fundamental frequency by an octave and restore the even harmonics 21. Carefully closing the bottom of an open pipe so that its length doesn t change will: a. lower the fundamental frequency by an octave and remove the even harmonics b. lower the fundamental frequency by an octave and restore the even harmonics c. raise the fundamental frequency by an octave and remove the even harmonics d. raise the fundamental frequency by an octave and restore the even harmonics

3 22. Let s say you want to make a tube, closed at one end, that has a fundamental frequency of 262 Hz. Let s assume that the speed of sound is 343 m/s and that the diameter of the tube is 4.0 cm. What length would you cut the tube? a m b m c m d m e m 23. A metal bar is being used as part of an idiophone. Which of the following changes would create a higher pitch when the bar is struck? a. increasing the length of the bar e. a and b b. decreasing the length of the bar f. a and c c. increasing the thickness of the bar g. b and c d. decreasing the thickness of the bar h. b and d 24. If the bar in the previous problem were cut in half, the pitch would a. increase by an octave d. decrease by an octave b increase by less than an octave e. decrease by less than an octave c. increase by more than an octave f. decrease by more than an octave 25. The length of the low C bar is 30.0 cm. What is the length of the high C bar? a cm b cm c cm d cm 26. What would be the effect on the fundamental frequency of a bar if you were to sand it down so that its thickness was uniformly decreased? a. decrease proportionately c. increase proportionately b. decrease, but not proportionately d. increase, but not proportionately The remaining multiple-choice questions are for honors physics only. 27. Let s say you calculate the acoustic length a closed pipe needs to be in order to play a particular frequency. If you then ignore the end effect and cut the pipe at the acoustic length, how will the tones it produces sound? a. flatter than calculated, but only for the first mode b. flatter than calculated, for all modes c. sharper than calculated, but only for the first mode d. sharper than calculated for all modes 28. You hear three harmonics in order from a wind instrument: 300 Hz, 500 Hz, and 700 Hz. Which best describes the pipe? a. closed pipe with a fundamental frequency of 100 Hz b. closed pipe with a fundamental frequency of 300 Hz c. open pipe with a fundamental frequency of 100 Hz d. open pipe with a fundamental frequency of 300 Hz 29. You hear three harmonics in order from a wind instrument: 300 Hz, 400 Hz, and 500 Hz. Which best describes the pipe? a. closed pipe with a fundamental frequency of 100 Hz b. closed pipe with a fundamental frequency of 300 Hz c. open pipe with a fundamental frequency of 100 Hz d. open pipe with a fundamental frequency of 300 Hz 30. The wavelengths of the sounds (fundamental frequency) produced by two closed pipes are 6 m and 7 m. What beat frequency is heard when the horns are played on a day when the speed of sound is 340 m/s? a. 5 Hz b. 6 Hz c. 7 Hz d. 8 Hz 31. What are the wavelengths of the three lowest tones in a closed pipe with length, L? a. 4L, 2L, L b. 2L, L, L/2 c. 2L, L, 2L/3 d. 4L, 4L/3, 4L/5

32. (Regular Physics) The simple stringed instrument pictured below plays the note C 2 (65.4 Hz) when the string is vibrating in its first mode. Tuners Nut Bridge a.

4 32. (Regular Physics) The simple stringed instrument pictured below plays the note C 2 (65.4 Hz) when the string is vibrating in its first mode. Tuners Nut Bridge a. What is the speed of the waves on the string? b. Calculate the place to fret the guitar string so that it plays G 2. Make a fret line on the guitar neck at this point. 32. (Honors Physics) This question pertains to the very simple stringed instrument shown below. Its two strings are attached at the nut and bridge and their tension can be adjusted with the tuners shown. The top string plays A 4 and the bottom string plays A 5. You will need to make measurements on this drawing. Tuners Nut Bridge a. The tension in the A 4 string is 100 N. What is the linear mass density of the string? b. The nut and bridge are shown below. If the A 4 string is plucked, it will vibrate in many standing wave configurations simultaneously. Draw the standing wave that produces the third harmonic. c. What note on the 12-tone Equal Tempered scale is this third harmonic of the A 4 string? Explain, or show work to justify your answer. d. What overtone is this harmonic? e. When the two strings are plucked together, the interval produced is an octave. Now draw two lines on the body of the instrument to indicate the two positions where you could fret the A 4 string to produce a musical fifth when the two strings are plucked together. Label these lines and show work below to justify your answer. f. Fretting the A 4 string will only produce higher notes. If you wanted to create a note lower than A 4, you would need to adjust the tension in the string. What would the tension need to be in order to produce the note A 3? 33. List the notes played when this chord is strummed: a. b. This chord sounds good when its notes are played because it produces certain consonant intervals? What are six of these intervals (and which notes produce these intervals)? X X E 2 A 2 D 3 G 3 B 3 E 4

5 C E G B 34. The pipes above are like the saliva-covered ones you were contaminated by in class. Like in the lab, the C pipe will be empty. The temperature is 25 C a. Measure the C pipe and use it to calculate the frequency it would make if you blew over the top of it. b. Use the frequency from above to calculate the frequencies of the other three pipes. E G B c. Calculate the lengths of the other three pipes and make a mark in each pipe showing the level to which water should be added. 35. Two organ pipes are located in the space below, one with both ends open and one with one end closed. Show the standing waves present in the pipes if they are both producing the 7 th harmonic. Closed 36. The wooden bar below will be used in a xylophone with both ends of the bar free to vibrate. The speed of sound in the bar is 3,500 m/s. a. What note on the Equal Tempered Scale does this pipe produce? b. How long would the pipe need to be in order to produce a tone one octave higher?

Music. Sound Part II

Music. Sound Part II Music Sound Part II What is the study of sound called? Acoustics What is the difference between music and noise? Music: Sound that follows a regular pattern; a mixture of frequencies which have a clear