PRINT YOUR NAME. D 1. What is the wavelength of the wave? (A) 0.5 m (B) 1 m (C) 1.5 m (D) 2 m (E) 3 m

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1 PRINT YOUR NAME The figure to the right shows a snapshot of the displacement of air in a standing wave on a 1.5 m organ pipe. The following questions refer to this figure. D 1. What is the wavelength of the wave? (A) 0.5 m (B) 1 m (C) 1.5 m (D) 2 m (E) 3 m A 2. What is the amplitude? (A) 3 nm (B) 5 nm (C) 6 nm (D) 9 nm (E) 36 nm B 3. If a guitar string played the same frequency you could distinguish its sound from the organ pipe by (A) the position of the nodes and antinodes (B) the pattern of overtones (C) the wavelength of the fundamental (D) speed of the waves A 4. The pipe is (A) open at 0 m, closed at 1.5 m (C) closed at 0 m, open at 1.5 m (B) open at 0 m, open at 1.5 m (D) closed at 0 m, closed at 1.5 m B 5. If I were to change the temperature of the air in the pipe (A) only the velocity of the wave changes (B) the velocity of the wave and the frequency change, but the wavelength stays the same (C) the velocity changes, the wavelength changes, and the frequency stays the same (D) velocity, frequency and wavelength all change (E) nothing changes. C 6. Which is true? (A) There is an antinode at 0.5 m. (B) There is only an antinode 1 m (C) There are antinodes at only 0 and 1 m. (D) There are antinodes at only 0.5 m and 1.5 m (E) There are antinodes at 0, 0.5 m, 1 m and 1.5 m C 7. In the next overtone there will be an antinode at (A) 0.3 m (B) 0.5 m (C) 0.6 m (D) 1.0 m (E) 1.5 m 1

2 PRINT YOUR NAME ALTERNATE VERSION The figure to the right shows a snapshot of the displacement of a standing wave on a 1.5 m organ pipe. The following questions to this figure. air in refer B 8. What is the wavelength of the wave? (A) 0.5 m (B) 1 m (C) 1.5 m (D) 2 m (E) 3 m A 9. What is the amplitude? (A) 3 nm (B) 5 nm (C) 6 nm (D) 9 nm (E) 36 nm B_10. If a guitar string played the same frequency you could distinguish its sound from the organ pipe by (A) the position of the nodes and antinodes (B) the pattern of overtones (C) the wavelength of the fundamental (D) speed of the waves B 11. The pipe is (A) open at 0 m, closed at 1.5 m (C) closed at 0 m, open at 1.5 m (B) open at 0 m, open at 1.5 m (D) closed at 0 m, closed at 1.5 m B_12. If I were to change the temperature of the air in the pipe (A) only the velocity of the wave changes (B) the velocity of the wave and the frequency change, but the wavelength stays the same (C) the velocity changes, the wavelength changes, and the frequency stays the same (D) velocity, frequency and wavelength all change (E) nothing changes E 13. Which is true? (A) There is an antinode at 0.25 m. (B) There are antinodes at only 0 and 1.5 m (C) There are antinodes at only 1 m and 1.5 m. (D) There are only 3 antinodes shown. (E) There are antinodes at 0, 0.5 m, 1 m and 1.5 m C 14. In the next overtone there will be an antinode at (A) 0.25 m (B) 0.5 m (C) 0.75 m (D) 1.0 m (E) 1.25 m 2

3 PRINT YOUR NAME Dolphins, despite weighing 1000 N, can float underwater at neutral buoyancy. They can communicate and echo- locate with a variety of sounds made by passing air through the phonic lips which are part of a structure in their heads similar to nasal passages. As the air passes between the phonic lip membranes, they move together, causing the surrounding tissue to vibrate. The dolphin can precisely regulate these vibrations, controlling the sounds in frequencies and intensity. Dolphin sounds can be quite loud certain clicks can be up to 220 db and yet dolphin hearing is quite sensitive. Not only can they hear softer sounds, their hearing extends from 75 Hz up to 160 khz. The high frequencies emitted allow the dolphins to detect small features under water. Sounds which the dolphins hear are conducted to the dolphin s middle and inner ear by two channels of fat connected to the jaw rather than external ears. The following questions refer to the above paragraph. _A 8. If the air moved faster as it went between the phonic lip membranes, they would (A) move closer together (B) move further apart (C) not change their separation B_9. Dolphins are said to be able to hear sounds 100 times weaker in intensity than humans can detect. This could be due to (A) the higher frequencies they detect (B) the larger area of their hearing apparatus (C) the higher speed of sound in water A_10. To study dolphin behavior, a group of marine biologists created a mechanical replica that is the same size but weighs 3000 N. (It is to be supported by wires from a boat on the surface) The buoyant force on the replica is (A) 1000 N (B) 2000 N (C) 3000 N (D) 4000 N (E) 5000 N _B_11 Frightened by the mechanical replica that has been lowered near it, a dolphin swims away at 12 m/s, emitting warning sounds at 100 Hz. What frequency is heard by the microphones inside the replica? (A) 96.6 Hz (B) 99.2 Hz (C) 100 Hz (D) Hz (E) Hz A_12. What is the smallest wavelength a dolphin can hear? (A) 0.01 m (B) 0.2 m (C) 5 m (D) 10 m (E) 19 m B_13. What is the intensity of the loudest sounds dolphins make? (A) 1 W/m 2 (B) W/m 2 (C) W/m 2 (D) W/m 2 (E) W/m 2 _D 14. If the dolphin is 120 m below sea level, how much pressure does the water exert on the blowhole? (A) 1.2 x 10 3 (B) 1.2 x10 4 (C) 1.2 x 10 5 (D) 1.2 x 10 6 (E) 1.2 x

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