Learning Goal: To understand the nature of a sound wave, including its properties: frequency, wavelength, loudness, pitch, and timbre Sound is a phenomenon that we experience constantly in our everyday life. Therefore, it is important to understand the physical nature of a sound wave and its properties to correct common misconceptions about sound propagation Most generally, a sound wave is a longitudinal wave that propagates in a medium (i.e., air). The particles in the medium oscillate back and forth along the direction of motion of the wave. This displacement of the particles generates a sequence of compressions and rarefactions of the medium. Thus, a sound wave can also be described in terms of pressure variations that travel through the medium. The pressure fluctuates at the same frequency with which the particles' positions oscillate When the human ear perceives sound, it recognizes a series of pressure. fluctuations rather than displacements of individual air particles Figure FIMM B 0 < 1 of 2 > A ▾ Part A Based on the information presented in the introduction of this problem, what is a sound wave? ▾ O Propagation of sound particles that are different from the particles that comprise the medium O Propagation of energy that does not require a medium O Propagation of pressure fluctuations in a medium O Propagation of energy that passes through empty spaces between the particles that comprise the medium Submit Part B Complete previous part(s) Part C Does air play a role in the propagation of the human voice from one end of a lecture hall to the other? ▸ View Available Hint(s) O yes O no Submit Request Answer Part D The graphs shown in (Eigure 1) represent the entirety of three separate pressure variation vs time recordings by a microphone. Which could correspond to a sound wave? Enter the letters of all the correct answers in alphabetical order. Do not use commas. For example, if you think all three graphs could represent sound waves, enter ABC. ▸ View Available Hint(s) Cubot

K 2. Resonances in a Tube A student is given a tube of unknown length and cannot tell whether the ends of the tube are open or closed. Given a tunable sound generator the student measures the frequencies of the two lowest resonances in the tube to be 235 Hz and 587 Hz. a. Explain why this student must be mistaken in the measurement. b. Is it possible that the student measured the lowest frequency correctly and simply missed some resonances between the two given above? If so, what would those missed frequencies be and what conclusion about end conditions can you reach? If not, why not?

QUESTION 2 Which of the following media cannot support a transverse wave? a. The atmosphere b. A steel bar O c. An aluminum rod d. The crust of the earth e. A lake

standing wave

q18

You try to form standing waves in an air column by using a tuning fork. How would you know that you hit a resonance at a certain length? Select all the correct answers. Select one or more: a. The sound frequency would decrease b. The sound would get quieter c. The sound would get louder d. The sound frequency would increase

Part 1: Trains with passengers A railroad train is traveling at 34.2 m/s in still air. The frequency of the note emitted by the train whistle is 220 Hz. The air temperature is -9°C. A.) What frequency is heard by a passenger on a train moving in the opposite direction to the first at 35.8 m/s and approaching the first? B.) What frequency is heard by a passenger on a train moving in the opposite direction to the first at 35.8 m/s and receding from the first?

Group Problem Chapter 18 Two sinusoidal waves in a string are defined by the wave functions with x and y in cm (so k is in rad/cm) and t in s. yı(x,t) = 2.10 sin (18.0x – 31.0t) y2(x,t) = 2.10 sin (30.0x – 45.0t) a) What is the phase difference between these two waves at the point x1=5.00cm and tj=2.00s? (Pick an angle between 0° and 360°.) b) What is the positive x value closest to the origin for which the two arguments differ by +(2n+1)n at t1? At that location the two waves destructively interfere. (Hint: it's not the n=0 case!)

Superposition and Standing Waves A standing wave occurs when two travelling waves with the same wavelength and wave speed pass through each other in opposite directions. Mathematically the first wave is written as: Y, (x, t) = A cos(kx – wt) and the second wave: Y,(x, t) = A cos(kx + wt) where the wave number, k = 2/2, the natural frequency w = 27/r, and A and T are the wavelength and period of the waves, respectively. The positive and negative signs of w show that the waves are travelling in opposite directions. Demonstrate that the sum of these two waves, Ysum = Y1 + Y2, results in a sinusoidal wave, Y(x) with a wavelength A and an amplitude that is twice that of each wave individually. Furthermore, as time advances, the amplitude is oscillating between +A and -A with a period, T. Repeat the summation, only now assume the other harmonic wave form: Y, (x, t) = A sin(kx – wt) and the second wave: Y2(x, t) = A sin(kx + wt) The following trigonometric identities may be helpful: sin(a +…

ment PRINTER VERSION 1 BACK NEXT Chapter 16, Problem 024 GO A wave traveling along the x axis is described mathematically by the equation y = 0.17sin(2.3nt + 0.68nx), where y is the displacement (in meters), t is in seconds, and x is in meters. What is the speed of the wave? %3D Number Units the tolerance is +/-5% GO TUTORIAL LINK TO TEXT By accessing this Question Assistance, you will learn while you earn points based on the Point Potential Policy set by your instructor. Question Attempts: 0 of 6 used SAVE FOR LATER SUBMIT ANSWER MacBook Pro Q Search or tyne URI