Two sound sources oscillate in phase with the same amplitude A. They are separated in space by 6 - What is the amplitude (as a multiple of A) of the resultant wave formed from the two sources at a point that is on the line that passes through the sources but is not between the sources?

A particular whistle produces sound by setting up the fundamental standing wave in an air column 7.10 cm long. The tube is closed at one end. The whistle blower is riding in a car moving away from you at  25m/s What frequency do you hear?

O 1m Two sinusoidal waves of wavelength A = 2/3 m and amplitude A = 6 cm and differing with their phase constant, are travelling to the right with same velocity v = 60 m/s. The resultant wave function y res (x,t) will have the form: %3D O y_res (x,t) = 12(cm) cos(p/2) sin(150tx-3rt+p/2). O y_res (x,t) = 12(cm) cos(p/2) sin(3TX+150rt+9/2). %3D O y_res (x,t) = 12(cm) cos(p/2) sin(150rtx+3tt+p/2). O y-res (x,t) = 12(cm) cos(p/2) sin(3Ttx-150rt+q/2). O y_res (x,t) = 12(cm) cos(p/2) sin(3Ttx-180Ttt=p/2). %3D Two sinusoidal waves travelling in the same direction with the same amplitude.

A 30 Hz sound is annoying or dissonant to the ear. If one clarinet plays a sound at a frequency of 360 Hz, at what frequencies (more than one) might another clarinet simultaneously play so the dissonant 30 Hz beats are created? Explain.

ZOOM + 1) Suppose we have an air column 80cm long with one open end and one closed end. (a) Find (i.e. derive) an expression for the resonant frequencies of the air column in terms of the length L of the air column, the speed of sound v, and the harmonic number n. Don't simply write the equation – show me how you obtain it by sketching several resonant standing waves. (b) What are the three lowest resonant frequencies in this air column (numerical values)? Take the speed of sound in air to be 343 m/s.

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1. The low-frequency speaker of a stereo set has a surface area of 0.05 m and produces 1 W of acoustical power. (a) What is the intensity at the speaker? (b) If the speaker projects sound uniformly in all directions, at what distance from the speaker is the W intensity 0.26 -? m2 Hint: If the sound projects uniformly in all directions, after traveling a distance r it is uniformly distributed over a sphere of area r. What is the surface area of a sphere of radius r? W (a) Intensity: m? (b) Distance (radius), r: m

O 1.2m m/s Two identical sinusoidal waves with frequency of 20 Hz travel in the same direction at the same speed. The two waves originate from the same point but with a time difference At. The amplitude of the resultant wave is Ares = AV2. The minimum possible time difference between the starting moments of the two waves is, At =: O 1/120 sec O 0.477 sec O 1/80 sec O 0.716 sec The figure below shows the maximum displacement for a standing wave pattern. The earliest time between the two flashes (the solid and the dotted lines) is 0.05 s. The wave function describing the standing wave pattern shown in the figure below is:

The equation resultant wave from the superposition of two waves propagating in opposite directions is: y = 0.4 sin (4nx) Cos (2nt) The point situated at the position x=0.4m is a: A- Node B- Anti – Node C- Arbitrary point ( Not node, neither anti – Node) А В C