1. Waves / Sound / Light Chapter 14, 15, and 16

2. True / False  ____1. Destructive interference between two superimposed waves can result in a node, or point with no displacement.  ____2. A point on a wave completes one cycle every 5 seconds. The frequency of this wave is 1/5 seconds.  ____3. The period of a pendulum is directly proportional to the mass of the bob.  ____4. The differences in air pressure that create a sound wave are the result of differences in the velocities of air particles.  ____5. Sound waves will travel faster through a wooden table than through the air.  ____6. Because of the Doppler effect, an observer will hear a sound moving away from her as being higher in pitch.

3. True/False  ____7. In a sound wave, the wavelength is equivalent to the distance from a region of high pressure to the region of mean pressure.  ____8. Sound travels faster on a cold day than on a warm day.  ____9. A closed-pipe resonator is closed at both ends.  ____10. The fundamental frequency of a pipe is the lowest resonant frequency.  ____11. Light always travels in a straight line.  ____12. A light-year is a unit that measures time.

4. Multiple Choice  ____13. Which scenario would result in a rise in the pitch being observed?  A. The observer moves away from a stationary source.  B. The source moves away from a stationary observer.  C. A source moving away and an observer suddenly stops.  D. The observer and the source move in the same direction at the same speed.  ____14. Which describes a sound wave?  A. A sound wave travels in a vacuum.  B. A sound wave is a longitudinal wave.  C. A sound wave is an electromagnetic wave.  D. A sound wave has one constant speed.

5. Multiple Choice  ____15. Which type of resonator has harmonics in whole-number multiples of the fundamental?  A. closed-pipe resonators  C. strings  B. open-pipe resonators  D. both strings and open-pipe resonators  ____16. Which is the purpose of resonance in musical instruments?  A. increase the pitch  C. make the sound louder  B. decrease the pitch  D. make the sound softer

6. Multiple Choice  ____17. Which is decreased when the string of a stringed instrument is loosened?  A. timbre  C. wavelength  B. pitch  D. loudness  ____18. What is the formula to find speed of light?  A. c = /f  C. c = f/  B. c = f  D. 2 /f

7. Multiple Choice  ____19. Which term describes a material that does not allow light to be transmitted?  A. translucent  C. polarized  B. transparent  D. opaque  ____20. Which kind of pigment reflects two primary light colors and absorbs one?  A. primary pigment  C. complementary pigments  B. secondary pigment  D. both primary and secondary pigments

8. You hear an increasing pitch of an ambulance, but it is not moving. vpvp v a = 0 vpvp vava v p = 0 vava A D B C

9. If these two waves were moving through water at the same time, what would the water look like? A B C D x x Wave 1 Wave 2

10. What is its speed of this wave? Time (sec) 12 A.1/2 m/s B.2 m/s C.5 m/s D.20 m/s E.Not enough information