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Suppose a flutist plays a 523-Hz C note with first harmonic displacement amplitude A1 = 100 nm. From Figure 17.21b read, by proportion, the displacement amplitudes of harmonics 2 through 7. Take these as the values, A2 through A7 in the Fourier analysis of the sound and assume
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- At a rock concert, the sound intensity 1.0 m in front of the bank of loudspeakers is 0.10 W/m2. A fan is 30 m from the loudspeakers. Her eardrums have a diameter of 8.4 mm. How much sound energy is transferred to each eardrum in 1.0 second?arrow_forwardThe speed of sound in a solid medium is 15 times greater than that in air. If the frequency of a wave in the solid is 61 kHz, then what is the wavelength? (The speed of sound in air is 344 m/s.)arrow_forwardThe frequency of the highest note on the piano is 4,186 Hz. a) How many harmonics of that note can we hear? (HINT: harmonics of a note have frequencies equal to 2, 3, 4, … times that of the fundamental note.) b) How many harmonics of the note one octave below it can we hear? (HINT: the note one octave below has ó the frequency.) [we can hear 4 harmonics; we can hear 9 harmonics]arrow_forward
- Calculate the pressure amplitude (in m) of a 45 kHz sound wave in pure hydrogen if it has adisplacement amplitude of 1.5 mm. (ρH2 = 0.08 kg/m3, v = 1286 m/s.)arrow_forwardOn a hot 93.2 F (307 K) day at a racetrack, a Formula One racecar is traveling at a speed of 1.55 x 10^2 mph (69.3 m/s) away from a stationary siren emitting sound waves at a frequency of 3.10 x 10^2 Hz. (a) Determine the sound speed for the given temperature. ( enter your answer to at least one decimal place.) (b) what frequency did the race car driver hear?arrow_forwardFor the scenario in Question 9 with the speed of eagle 11.61 m/s, what frequency does the blackbird hear (in Hz) after the eagle passes the blackbird? Question 9= An eagle flying at 28 m/s emits a cry whose frequency is 370 Hz. A blackbird is moving in the same direction as the eagle at 10.02 m/s. (Assume the speed of sound is 343 m/s). What frequency does the blackbird hear (in Hz) as the eagle approaches the blackbird?arrow_forward
- A flute is designed so that it plays a frequency of 268.2 Hz, when all the holes are covered and the temperature is 18.2°C. (a) What is the speed of sound in the flute? A flute is designed so that it plays a frequency of 268.2 Hz, when all the holes are covered and the temperature is 18.2°C. (b) What is the wavelength of the first harmonic? Consider the flute to be a pipe open at both ends A flute is designed so that it plays a frequency of 268.2 Hz, when all the holes are covered and the temperature is 18.2°C. (c)Consider the flute to be a pipe open at both ends and find its length, assuming this frequency is the fundamental frequency A flute is designed so that it plays a frequency of 268.2 Hz, when all the holes are covered and the temperature is 18.2°C. A second player, nearby in a colder room, also attempts to play middle C on an identical flute. A beat frequency of 3.00 beats/s is heard. (e) What is the speed of sound in the second room? A flute is designed so that it plays a…arrow_forwardSuppose a bat emits ultrasound at frequency fbe = 81.28 kHz while flying with velocity vb = (12.16 m/s)i as it chases a moth that flies with velocity vm = (3 m/s)i. What frequency fmd does the moth detect? What frequency fbd does the bat detect in the returning echo from the moth? Assume the speed of sound is 343 m/s. Round all your answers off to two decimal places.arrow_forwardThe frequency of the highest note on the piano is 4,186 Hz. a) How many harmonics of that note can we hear? (HINT: harmonics of a note have frequencies equal to 2, 3, 4, … times that of the fundamental note.) [answer: we can hear 4 harmonics] b) How many harmonics of the note one octave below it can we hear? (HINT: the note one octave below has 1/2 the frequency.) [answer: we can hear 9 harmonics]arrow_forward
- The electrical power needed to operate a speaker in your audio system is 18.7 W. If this speaker has a circular opening with a radius of 0.0743 m and the average sound intensity at the opening is 22.1 W/m2, determine the ratio of sound output power Psound to electrical input power Pelectrical. Psound Pelectricalarrow_forwardAsaad, a grade 11 student, completed a lab activity to find the speed of sound in air using a closed-air column. He measured the temperature of the room to be 21 °C. Using a tuning fork with a frequency of 1040 Hz, he obtained the following resonant lengths for the closed air column:Observations:L1= 7.4 cmL2= 22.5 cmL3 = 36.7 cm Questions:a) Use the resonant lengths to do three calculations to find the wavelength. Find the averagewavelength and use that in further calculations.b) Using the wave equation, what is the speed of sound in the air column?c) What is the theoretical speed of sound in the room according to the temperature?arrow_forwardYour experiments on a particular insulator indicate that at 20°C, the average speed of sound in the insulator is vi = 8500 m/s and its bulk modulus is Bi = 370 GPa. Experimental results from your colleague show that a certain metal alloy has a density of ρm = 6500 kg/m3 and a bulk modulus of Bm = 110 GPa. a. Calculate the density of the insulator ρi in kilograms per cubic meter. b. Calculate the speed of sound vm in the metal alloy in meters per second. c. If the sound traveled as indicated in the structure in figure 1, emerging from the insulator at time ti and the alloy at time tm, determine Δt = tm - ti in seconds. The length of the structure is L = 1.0 m. d. Find the total amount of time t, in seconds, it takes to travel through the structure as indicated in figure 2. The length of the structure is L = 1.0 m.arrow_forward
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning