1 2 3 4 5

1. Sketch A shows two identical pulses traveling in opposite directions along a string, each with a speed of 1.0 cm/s. After 4.0 s, the string will look like which of the other sketches? • 1 • 2 • 3 • 4 • 5

2. Sketch A shows two identical pulses traveling in opposite directions along a string, each with a speed of 1.0 cm/s. After 4.0 s, the string will look like which of the other sketches? • 1 • 2 • 3 • 4 • 5

3. Why does your voice change pitch when you speak after inhaling the contents of a helium-filled balloon? • The helium decreases the effective length of your vocal cords, so their fundamental frequency is increased. • The helium increases the stiffness of your vocal cords, so their fundamental frequency is increased. • The speed of sound in helium is higher than the speed of sound in air, so the fundamental frequency of your throat and mouth cavity is increased. • The speed of sound in helium is lower than the speed of sound in air, so the frequency of the sound released into the air is increased. • Helium is a lighter gas than air, so the resulting buoyancy force causes the pitch to rise.

4. Why does your voice change pitch when you speak after inhaling the contents of a helium-filled balloon? • The helium decreases the effective length of your vocal cords, so their fundamental frequency is increased. • The helium increases the stiffness of your vocal cords, so their fundamental frequency is increased. • The speed of sound in helium is higher than the speed of sound in air, so the fundamental frequency of your throat and mouth cavity is increased. • The speed of sound in helium is lower than the speed of sound in air, so the frequency of the sound released into the air is increased. • Helium is a lighter gas than air, so the resulting buoyancy force causes the pitch to rise.

5. The figure represents a string of length L, fixed at both ends, vibrating in several harmonics. Which string shows the 4th harmonic?

6. The figure represents a string of length L, fixed at both ends, vibrating in several harmonics. Which string shows the 4th harmonic?

7. The figure represents a string of length L, fixed at both ends, vibrating in several harmonics. Which string shows the 3rd harmonic?

8. The figure represents a string of length L, fixed at both ends, vibrating in several harmonics. Which string shows the 3rd harmonic?

9. The figure shows several modes of vibration of a string fixed at both ends. The mode of vibration that represents the fifth harmonic is • 1 • 2 • 3 • 4 • None of these is correct.

10. The figure shows several modes of vibration of a string fixed at both ends. The mode of vibration that represents the fifth harmonic is • 1 • 2 • 3 • 4 • None of these is correct.

11. The fundamental frequency of a vibrating string is f1. If the tension in the string is doubled, the fundamental frequency becomes

12. The fundamental frequency of a vibrating string is f1. If the tension in the string is doubled, the fundamental frequency becomes

13. The fundamental frequency of a vibrating string is f1. If the tension in the string is increased by 50% while the linear density is held constant, the fundamental frequency becomes • f1 • 1.2f1 • 1.5f1 • 1.7f1 • 2f1

14. The fundamental frequency of a vibrating string is f1. If the tension in the string is increased by 50% while the linear density is held constant, the fundamental frequency becomes • f1 • 1.2f1 • 1.5f1 • 1.7f1 • 2f1

15. A stretched string is fixed at points 1 and 5. When it is vibrating at the second harmonic frequency, the nodes of the standing wave are at points • 1 and 5. • 1, 3, and 5. • 1 and 3. • 2 and 4. • 1, 2, 3, 4, and 5.

16. A stretched string is fixed at points 1 and 5. When it is vibrating at the second harmonic frequency, the nodes of the standing wave are at points • 1 and 5. • 1, 3, and 5. • 1 and 3. • 2 and 4. • 1, 2, 3, 4, and 5.

17. A stretched string is fixed at points 1 and 5. When it is vibrating in its first harmonic frequency, the nodes are at points • 1 and 5 only. • 1, 3, and 5. • 2 and 4. • 2, 3, and 4. • 1, 2, 3, 4, and 5.

18. A stretched string is fixed at points 1 and 5. When it is vibrating in its first harmonic frequency, the nodes are at points • 1 and 5 only. • 1, 3, and 5. • 2 and 4. • 2, 3, and 4. • 1, 2, 3, 4, and 5.

19. The figure shows a standing wave in a pipe that is closed at one end. The frequency associated with this wave pattern is called the • first harmonic. • second harmonic. • third harmonic. • fourth harmonic. • fifth harmonic.

20. The figure shows a standing wave in a pipe that is closed at one end. The frequency associated with this wave pattern is called the • first harmonic. • second harmonic. • third harmonic. • fourth harmonic. • fifth harmonic.

21. Of the sound sources shown, that which is vibrating with its first harmonic is • the whistle. • the organ pipe. • the vibrating string. • the vibrating rod. • None of these.

22. Of the sound sources shown, that which is vibrating with its first harmonic is • the whistle. • the organ pipe. • the vibrating string. • the vibrating rod. • None of these.

23. Of the sound sources shown, that which is vibrating with its first harmonic is the • whistle. • organ pipe. • vibrating string. • vibrating rod. • vibrating spring.

24. Of the sound sources shown, that which is vibrating with its first harmonic is the • whistle. • organ pipe. • vibrating string. • vibrating rod. • vibrating spring.

25. When an organ pipe, which is closed at one end only, vibrates with a frequency that is three times its fundamental (first harmonic) frequency, • the sound produced travels at three times its former speed. • the sound produced is its fifth harmonic. • beats are produced. • the sound produced has one-third its former wavelength. • the closed end is a displacement antinode.

26. When an organ pipe, which is closed at one end only, vibrates with a frequency that is three times its fundamental (first harmonic) frequency, • the sound produced travels at three times its former speed. • the sound produced is its fifth harmonic. • beats are produced. • the sound produced has one-third its former wavelength. • the closed end is a displacement antinode.

27. The air in a closed organ pipe vibrates as shown. The length of the pipe is 3.0 m. The frequency of vibration is 80 Hz. The speed of sound in the pipe is approximately • 80 m/s • 0.16 km/s • 0.24 km/s • 0.32 km/s • 0.96 km/s

28. The air in a closed organ pipe vibrates as shown. The length of the pipe is 3.0 m. The frequency of vibration is 80 Hz. The speed of sound in the pipe is approximately • 80 m/s • 0.16 km/s • 0.24 km/s • 0.32 km/s • 0.96 km/s

29. A string fixed at both ends is vibrating in a standing wave. There are three nodes between the ends of the string, not including those on the ends. The string is vibrating at a frequency that is its • fundamental. • second harmonic. • third harmonic. • fourth harmonic. • fifth harmonic.

30. A string fixed at both ends is vibrating in a standing wave. There are three nodes between the ends of the string, not including those on the ends. The string is vibrating at a frequency that is its • fundamental. • second harmonic. • third harmonic. • fourth harmonic. • fifth harmonic.

31. On a standing-wave pattern, the distance between two consecutive nodes is d. The wavelength is • d/2 • d • 3d/2 • 2d • 4d

32. On a standing-wave pattern, the distance between two consecutive nodes is d. The wavelength is • d/2 • d • 3d/2 • 2d • 4d

33. A stretched string of length L, fixed at both ends, is vibrating in its third harmonic. How far from the end of the string can the blade of a screwdriver be placed against the string without disturbing the amplitude of the vibration? • L/6 • L/4 • L/5 • L/2 • L/3

34. A stretched string of length L, fixed at both ends, is vibrating in its third harmonic. How far from the end of the string can the blade of a screwdriver be placed against the string without disturbing the amplitude of the vibration? • L/6 • L/4 • L/5 • L/2 • L/3

35. In a pipe that is open at one end and closed at the other and that has a fundamental frequency of 256 Hz, which of the following frequencies cannot be produced? • 768 Hz • 1.28 kHz • 5.12 kHz • 19.7 kHz • All of these can be produced.

36. In a pipe that is open at one end and closed at the other and that has a fundamental frequency of 256 Hz, which of the following frequencies cannot be produced? • 768 Hz • 1.28 kHz • 5.12 kHz • 19.7 kHz • All of these can be produced.

37. The fundamental frequency of a pipe that has one end closed is 256 Hz. When both ends of the same pipe are opened, the fundamental frequency is • 64.0 Hz • 128 Hz • 256 Hz • 512 Hz • 1.02 kHz

38. The fundamental frequency of a pipe that has one end closed is 256 Hz. When both ends of the same pipe are opened, the fundamental frequency is • 64.0 Hz • 128 Hz • 256 Hz • 512 Hz • 1.02 kHz

39. A 1.00 m string fixed at both ends vibrates in its fundamental mode at 440 Hz. What is the speed of the waves on this string? • 220 m/s • 440 m/s • 660 m/s • 880 m/s • 1.10 km/s

40. A 1.00 m string fixed at both ends vibrates in its fundamental mode at 440 Hz. What is the speed of the waves on this string? • 220 m/s • 440 m/s • 660 m/s • 880 m/s • 1.10 km/s

41. The sound wave in an organ tube shown has a wavelength that is equal to the distance between • A and B. • A and C. • the nodes farthest apart. • the antinodes farthest apart. • None of these is correct.

42. The sound wave in an organ tube shown has a wavelength that is equal to the distance between • A and B. • A and C. • the nodes farthest apart. • the antinodes farthest apart. • None of these is correct.