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Essential Question Why/how does the sound from a passing car change?. http://www.kettering.edu/~drussell/Demos/doppler/doppler.html. Stationary Source and Stationary Observers. http://www.kettering.edu/~drussell/Demos/doppler/doppler.html. Stationary Source but Moving Observer.
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Essential Question Why/how does the sound from a passing car change?
http://www.kettering.edu/~drussell/Demos/doppler/doppler.htmlhttp://www.kettering.edu/~drussell/Demos/doppler/doppler.html
Stationary Source and Stationary Observers http://www.kettering.edu/~drussell/Demos/doppler/doppler.html
Stationary Source but Moving Observer http://www.kettering.edu/~drussell/Demos/doppler/doppler.html
Moving Source but Stationary Observer http://www.kettering.edu/~drussell/Demos/doppler/doppler.html
Moving Source but Stationary Observer Doppler Effect Car Passing RaceCar TrainPassing
DOPPLER (Δvelocity effect) • A stationary sound source is emitting a 550 Hz buzz. You ride your bike toward the sound at 5 m/s… what do you hear?
DOPPLER (Δwavelength effect) • You are standing on the side of the road as a police car approaches… it is traveling at 20 m/s and actually producing a 600 Hz siren… What do you hear?
Doppler Radar http://kfty.com/weather/interactive/
Doppler Effect: Sound… Moving source causes a change in frequency for stationary observers. What else might the Doppler Effect affect?
EXTREME "DOPPLER-like" Situations
http://www.kettering.edu/~drussell/Demos/doppler/doppler.htmlhttp://www.kettering.edu/~drussell/Demos/doppler/doppler.html
Source Moving FASTER than the waves it is making. http://www.kettering.edu/~drussell/Demos/doppler/doppler.html
Source Moving FASTER than the waves it is making. CrestCrest Crest + Crest Big fatty Crest
October 14 1947 Chuck Yeager – October 14, 1947
Source Moving FASTER than the waves it is making. CrestCrest Crest + Crest Big fatty Crest
http://www.kettering.edu/~drussell/Demos/doppler/doppler.htmlhttp://www.kettering.edu/~drussell/Demos/doppler/doppler.html
http://www.ctrl-c.liu.se/ftp/images/AVIATION/MILITARY/USA/f14/f14-3.jpghttp://www.ctrl-c.liu.se/ftp/images/AVIATION/MILITARY/USA/f14/f14-3.jpg F-14Tomcat http://www.mediacen.navy.mil/pubs/allhands/jan01/f14tomcat.jpg
SOUND Intensity dB – Decibels… better thought of as deci - Bells
Jet Engine at 30 m Threshold of Pain,Siren, Loud Rock Concert Lawn Mower Vacuum Cleaner Normal Conversation Mosquito Buzzing Whisper Rustling Leaves,Normal Breathing Threshold of hearing 140 dB 120 dB 100 dB 70 dB 50 dB 40 dB 20 dB 10 dB 0 Loudness of Sound 0 dB to 10 dB = 101 = 10 times louder = 101 10 dB to 20 dB = 10 times louder = 10*10 or 102 20 dB to 40 dB = 100 times louder = 10*10*10 or 103 40 dB to 70 dB = 1000 times louder = 105 70 dB to 120 dB = 100,000 x louder 15.2 dB to 48.4 dB = 48.4 – 15.2 = 33.2 = 103.32 = 2,089 x louder