Final Exam Help!!! Question 27 Multiple Choice 2 points By what factor should the length of a simple pendulum be changed in order to triple the period of vibration? 3 6 9 27 Question 28 Multiple Choice 2 points Each compression in the waveform of the longitudinal wave shown above corresponds to what feature of the transverse wave below it? wavelength crests troughs amplitude Question 29 Multiple Choice 2 points Each stretched region in the waveform of the longitudinal wave shown above corresponds to what feature of the transverse wave below it? wavelength crests troughs amplitude Question 30 Multiple Choice 2 points Which of the following most affects the wavelength of a mechanical wave moving through a medium? Assume that the frequency of the wave remains constant. the nature of the medium the amplitude the height of a crest the energy carried by the wave Question 31 Multiple Choice 2 points Suppose that two sound waves passing through the same medium have different wavelengths. Which of the following is most likely to be the reason for the differing wavelengths? the nature of the medium differences in amplitude differences in frequency the type of wave Question 32 Multiple Choice 2 points When two mechanical waves coincide, the amplitude of the resultant wave is always ____ the amplitudes of each wave alone. greater than less than the sum of the same as Question 33 Multiple Choice 2 points Sound waves are a part of the electromagnetic spectrum. do not require a medium for transmission. are longitudinal waves. are transverse waves. Question 34 Multiple Choice 2 points Which of the following is the region of a sound wave in which the density and pressure are greater than normal? rarefaction compression amplitude wavelength Question 35 Multiple Choice 2 points Of the following materials, sound waves travel fastest through helium at 0°C. air at 0°C. copper at 0°C. air at 100°C. Question 36 Multiple Choice 2 points In general, sound travels faster through solids than through gases. gases than through solids. gases than through liquids. empty space than through matter. Question 37 Multiple Choice 2 points A train moves down the track toward an observer. The sound from the train, as heard by the observer, is ____ the sound heard by a passenger on the train. the same as a different timbre than higher in pitch than lower in pitch than Question 38 Multiple Choice 2 points The Doppler effect occurs with only sound waves. only transverse waves. only water waves. all waves. Question 39 Multiple Choice 2 points At a distance of 3 m, the intensity of a sound will be ____ the intensity it was at a distance of 1 m. one-ninth one-third 3 times 9 times Question 40 Multiple Choice 2 points The intensity of a sound at any distance from the source is directly proportional to the sound's wavelength. pitch. power. frequency. Question 41 Multiple Choice 2 points When the frequency of a force applied to a system matches the natural frequency of vibration of the system, ____ occurs. damped vibration random vibration timbre resonance Question 42 Multiple Choice 2 points The Tacoma Narrows bridge collapsed in 1940 when winds caused ____ to build up in the bridge. a compression wave a longitudinal wave a standing wave friction Question 43 Multiple Choice 2 points If a guitar string has a fundamental frequency of 500 Hz, what is the frequency of its second harmonic? 250 Hz 750 Hz 1000 Hz 2000 Hz Question 44 Multiple Choice 2 points Four beats per second are heard when two notes are sounded. The frequency of one note is 420 Hz. Which of the following is a possible frequency of the other note? 418 Hz 105 Hz 416 Hz 1680 Hz Question 45 Essay 4 points A 0.10 kg piece of copper at an initial temperature of 95°C is dropped into 0.20 kg of water contained in a 0.28 kg aluminum calorimeter. The water and calorimeter are initially at 15°C. What is the final temperature of the system when it reaches equilibrium?