Question
A source of sound produces waves of wavelength 28cm. The source is moving with velocity 12 m/s due east. Find the apparent wavelength of wave received by observer on: (i) east (ii) west of source. Take velocity of sound in air as 336 m/s.
Solution
Here, we have
Wavelength, 
Velocity of the sound in air, 
(i) When the observer is on the east of train, the train moving due east will approach the observer.
The apparent wavelength of wave received by observer is, ![<pre>uncaught exception: <b>mkdir(): Permission denied (errno: 2) in /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/util/sys/Store.class.php at line #56mkdir(): Permission denied</b><br /><br />in file: /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/util/sys/Store.class.php line 56<br />#0 [internal function]: _hx_error_handler(2, 'mkdir(): Permis...', '/home/config_ad...', 56, Array)
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(ii) When the observer is on the west of train, the train moving due east will move away from the observer.
The apparent wavelength of wave received by observer is,
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#6 {main}</pre>](/application/zrc/images/qvar/PHEN11040299-4.png)
