1 / 10

9.5 The Doppler Effect

9.5 The Doppler Effect. The Doppler Effect. Apparent change in frequency of a sound relative to the object’s motion. As the source moves closer , observed frequency increases . As the source moves away , observed frequency decreases . Can occur when

Download Presentation

9.5 The Doppler Effect

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. 9.5 The Doppler Effect

  2. The Doppler Effect • Apparent change in frequency of a sound relative to the object’s motion. • As the source moves closer, observed frequency increases. • As the source moves away, observed frequency decreases. • Can occur when • Source is moving relative to a stationary observer • Observer is moving relative to a stationary source

  3. Stationary Source & Observer Moving Source http://www.fisica.uniud.it/~deangeli/applets/Multimedia/Waves_java/Doppler/doppler.htm

  4. Example 1 You are standing at a railway crossing. A train approaching at 125 km/h sounds its whistle. If the frequency of the whistle is 442 Hz and the air temperature is 20.0°C, what frequency do you hear when the train approaches you? When the train has passed you?

  5. Supersonic Travel Subsonic speed: less than the speed of sound in air Mach number: Mach = speed of object speed of sound Supersonic speed: when Mach > 1 http://www.fisica.uniud.it/~deangeli/applets/Multimedia/Waves_java/Doppler/doppler.htm

  6. Sound barrier: high pressure region produced when plane approaches Mach 1 A shock wave is produced when the place “breaks” through this barrier.

  7. Sonic boom • Explosive sound that radiates from aircraft travelling at supersonic speeds • Caused by constructive interference of spheres of sound waves that are left behind the aircraft The space shuttle, on re-entry: http://www.youtube.com/watch?v=lNL4HHFG8H4 http://www.youtube.com/watch?v=Oo_1HeravCY&feature=related http://www.youtube.com/watch?v=a1CU6VVE0AA&feature=related If time, Mythbusters: http://www.youtube.com/watch?v=GvtAElaDVz8

  8. Homework 9.5 Practise #1, 2 pg 435 9.5 Questions #2-6 pg 435

More Related