Re: Speed of sound at altitude and temp

[brian whatcott <inet@intellisys.net>]

As you can see, David Dockstader read a graph value from his CRC C&P 
which is markedly at variance with the expected value for -62degF

 As my 32nd edition seems to offer a reasonable value, I can only hope
that the typo (?) was caught in editions after the 48th...

Regards
brian whatcott


At 00:20 7/15/97 EDT, David Dockstader wrote:
> The formula Brian gives addresses temp, but not altitude.
> I looked up speed of sound in the index of my CRC Handbook of Chem & Physic
> (48th ed, hopefully in newer ed too) and found a neat graph of the speed of
> sound vs altitude for the real earth (I assume this is empirical but am not
> sure of this) At 35,000 ft it is 335m/s.  Interesting related graphs are
> Mean free path vs altitude and Collision Frequency vs Altitude.
>
>
> On Sat, 12 Jul 1997 12:19:15 brian whatcott said:
....
> > Enc Brit ( 14th edition, "sound") offers this empirical formula:
> > c = 331.3 x root(1 + t/273)
> >
> > c in meters/sec, temp in degC
> >
> > This is c = 741 x root(0.935 + 0.002t)
> >
> > c in mph, t in degF
> > ...

brian whatcott <inet@intellisys.net>
Altus OK