1. 1. Frequency times wavelength equals_________. Speed 2. Then number of complete wave cycles per unit time is called? Frequency 3. A ____________ is a region in the medium in which molecules are crowded together. Compression 4. The ability of an object to vibrate by absorbing energy at its natural frequency is called _________? Resonance WAVES & SOUND STUDY GUIDE

2. 5. The human perception of intensity is known as _________? Loudness 6. Sound waves are this kind of wave _________? Compressional waves 7. The speed of sound depends on? TemperatureDensityElasticity 8. Reflection of a wave occurs when the wave? Strikes a boundary and bounces back 9. The pitch of a sound depends on its? Frequency

3. 8. Amplitude is related to ? Wave energy 9. The loudness of a sound depends on? Amplitude 10. Refraction occurs because waves? Move at different speeds in different mediums 11. In rarefaction, the molecules of the medium are ? Spaced apart

4. 12. A wave in which the particles of the medium move at right angles to the direction of the wave is called? Transverse wave 13. You can hear a sound that is produced out of sight around the corner of a building because of ? Diffraction 13. The maximum displacement of molecules in a medium from their rest position is called? Amplitude 14. High pitch is produced by sounds that have? High frequency

5. 15. The ability of two or more waves to combine to form a new wave is __________ __________? Constructive interference 16. Any substance through which a wave is transmitted is called a ___________? Medium 17. When part of the Earth’s crust breaks, __________ waves pass through the Earth. Seismic 18. Sound travels the best and fastest through? Solids

6. 19. For the speed of a wave to remain constant, an increase in wavelength requires a corresponding _________? Decrease in frequency 20. All waves _________? Can transfer energy, but not matter 21.In a standing wave the point at which the medium doesn’t move is called the __________? Node 22. Sounds with frequencies under 20Hz are __________ Infrasonic

7. 23. The change in pitch of a sound caused by motion of either the sound source or receiver is called _? Doppler Effect 24. A wave in which the motion of the medium is parallel to the direction of the wave is called a ? Compressional wave 25. Finding objects by emitting sound waves and interpreting the reflected sound is known as ________? Echolocation 26. Sounds with frequencies above 20,000 HZ are? Ultrasonic waves

8. 27. A ______ is a region in the medium in which molecules are crowded together? Compression 28. _________ is used to locate objects underwater by the reflection of sound waves? Sonar 29. Can you sound in space? Why or why not? No, because sound needs a medium to travel through. 30. What is acoustics? The study of sound

9. 31. What is reverberation? The echoing effect produced by many reflections of sound. 32. How would you get rid of the echoes to enhance a sound system for a musical production? Add acoustic panels or carpets and drapes that will reduce reflection and decrease the echo effect 33. Compare and contrast transverse and compressional waves. Both have wavelength, frequency, amplitude, crests and troughs. Transverse waves do not require a medium, particles move at right angels to the medium, light Compressional- Mechanical waves, particles move parallel to the medium, sound

10. 34. How does density affect the speed of sound? Low density-speed is fast High density-slow speed 35. How does temperature affect the speed of sound? Low temperature-slow speed High temperature-high speed 36. How does elasticity affect the speed of sound? Low elasticity-slow speed High elasticity-fast speed

11. 37. Draw and label a transverse wave G-resting point; E-trough; F-crest; C-amplitude; D-wavelength

12. 38. What is the speed of a wave if the frequency is 300 Hz and the wavelength is 150m? S = λf S = (150)(300) = 45000 m/s 39. What is the wavelength of a 350 Hz wave traveling at 500m/s? S = λf λ = 1.4 meters 40. How many cycles per second would be characteristic of a 30 m wave traveling at 300 m/s? S = λf 10 cycles/sec (Hz)