Re: buoyant cannon balls

["Timothy J. Folkerts" <tim.folkerts@valpo.edu>]

On Fri, 31 Oct 1997 20:18:55 -0600 brian whatcott <inet@intellisys.net> 
wrote:

 
>  You can doubtless recall the cannon story about the Royal range trials.
> By degrees more powder was added to a cannon charge to increase its range -
> until a limiting charge, beyond which no more powder could induce an 
> increase in range. And that of course was an early brush with the speed of
> sound... 
I don't follow.  Bullets and cannon balls can travel faster than the 
speed of sound.  Why should the speed of sound be a limiting factor?

Not that I am any expert, but couldn't this be related to the 
combustion of the powder.  With a spark at one end, the powder can only 
burn so fast.  At some point, the powder won't all have burned by the 
time the cannon ball leaves.  Any more powder would just make a bigger 
bang after the cannon ball had left.


---  Tim


---------------------------------------------------------
Timothy J. Folkerts            email:  tim.folkerts@valpo.edu
Department of Physics          phone:  219-464-6634
Valparaiso University
Valparaiso, IN  46383