A droppler question: Calculating the frequency of sound waves.

An untethered(free) weather balloon travelling with the wind (at wind speed) emits a 1 khz sound wave. The wind is blowing with respect to the land due east at .25 times the speed of sound in air. If the free balloon is moving away (due east)from a tower at same height, what is the frequency of the sound detected at the tower? Take the speed of sound to be 340 m/s.

Hints- draw a picture. what is the preferred reference frame?

Solution Summary

A droppler question calculates the frequency of sound waves.

Two sound waves are emitted: y1, with frequency f1, and y2, with frequency f2, with other constants identical, as expressed below. Distances in meters, times in seconds, and angles in radians:
(1) y1 = .02 sin(8 Pi x - 108 Pi t) (2) y2= .02 sin (8 Pi x - 100 Pi t)
The two waves add to produce thesound perceived b

A train is approaching a station and blows its horn with a frequency of 200hz. If the train has a speed of 25 m/s and the speed of sound is 350 m/s, what is thefrequency of sound heard by the people standing on the platform
a. 190hz
b. 186hz
c. 210 hz
d. 200hz

A sound source and a person are separated by 1000m. Thesound source produces a frequency of 400Hz. Given speed of sound in air @ 343 m/s find:
1) Source moves toward person at 20 m/s, what frequency does the person hear?
2) If source stays still, but the person moves toward thesound source at 20 m/s, what frequency wil

A speaker fixed to a moving platform moves to a wall, emitting a steady sound with a frequency of 250Hz. A person on the platform, right next to the speaker detects thesound waves reflected off the wall, and those emitted by the speaker.
How fast should the platform move, vp, for the person to detect a beat frequency of 4.0

(See attached file for full problem description and figures)
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21.8
The figure shows a standing wave oscillating at 100 Hz on a string.
Part A : What is the wave speed?
21.5
A 40-cm-long tube has a 40-cm-long insert that can be pulled in and out. A vibrating tuning fork is held next to the tube. As the ins

The red light associated with the Aurora Borealis is emitted by excited oxygen atoms at 6.60 X 10-7 m. What is thefrequency of the light? Using scientific notation, (Round your answer to two decimal places) and write the exponent part as follows: x 10 to the _ power.

Please show work
1. In your own words, explain the meaning of the following terms:
a. Traverse waves
b. Longitudinal waves
c. Standing waves
d. Shock waves
2. Police use Doppler radar to detect speeding cars. Explain how the Doppler effect is used in this application.
3. A person in a cave emits a sound and rece

21. Units and Dimentions [Please refer to the attachment for the problem]
22. You hear a sound with level 80.0 dB and you are located 10.0 m from thesound source. What is the power being emitted by thesound source?
23. There is a 1.2 m distance between a crest and an adjacent trough in a series of waves on the surface of