#5244 NORM Future : Speed of sound depends on altitude

[Zarro Boogs per Child]

#5244: Speed of sound depends on altitude
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  Reporter:  jg                         |       Owner:  bemasc        
      Type:  defect                     |      Status:  closed        
  Priority:  normal                     |   Milestone:  Future Release
 Component:  acoustic-measure-activity  |     Version:  Build 649     
Resolution:  worksforme                 |    Keywords:                
  Verified:  0                          |  
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Changes (by bemasc):

  * status:  new => closed
  * resolution:  => worksforme


Comment:

 Replying to [ticket:5244 jg]:
 > Shall we say that presuming sea level is insufficient???

 Two things:
 1. No, it's totally sufficient.
 a. That model is very odd; it assumes that the sea-level temperature is 59
 Fahrenheit, everywhere, all the time.

 b. My code can account for pressure variation, if it's known.  The speed
 of sound at 25 C, humidity=0.6, at sea-level pressure, is 347.298 m/s.  At
 the same temperature and humidity, pressure equivalent to 3000 m, it's
 347.740.  That's a difference of 0.1%, or about as much error as you get
 by being wrong about the temperature by 1 degree F.

 2. I would love for you to tell me where I am (#4282).  That would allow
 me to account for the pressure, but more importantly, it would allow me to
 set default temperature and humidity to decent guesses, based on time of
 year and time of day.  If I had an internet connection, I could even look
 up the current weather conditions.

-- 
Ticket URL: <http://dev.laptop.org/ticket/5244#comment:1>
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