Re: Comet deflection

From: John Schilling (schillin_at_spock.usc.edu)
Date: 07/20/04 

Date: Tue, 20 Jul 2004 09:25:10 -0700
To: sci-military-moderated@moderators.isc.org

"Carl Alex Friis Nielsen" <cafn@get2net.dk> writes:

>Juergen Nieveler skrev i meddelelsen ...

>>The energy transferred would still be about the same, though...

>A 0,01 kg projectile moving at 300 m/s has a kinetic energy of 450 J
>A 10 kg projectile with a kinetic energy of 450 J moves at 0,3 m/s

Danger, Will Robinson! Math Error Detected! Danger, Danger!

A ten-kilogram projectile with a kinetic energy of 450 Joules will
have a velocity of 9.5 meters per second, twenty miles per hour or
thirty-five kilometers per hour for those more accustomed to thinking
in those terms.

>If both projectiles transfer their entire energy to your body, do you
>then have a preference for which you prefer to be hit by ?

Whichever one has the greatest projected surface area to spread the
impact over.

>While you could be hurt by the 10 kg projectile you could probably
>catch it unhurt if you were aware it was coming.

I'd like to see you try to catch the 10 kg, 450 J projectile. No,
rephrase that. I'd like to see someone I really don't like, try that
stunt. 

-- 
*John Schilling                    * "Anything worth doing,         *
*Member:AIAA,NRA,ACLU,SAS,LP       *  is worth doing for money"     *
*Chief Scientist & General Partner *    -13th Rule of Acquisition   *
*White Elephant Research, LLC      * "There is no substitute        *
*schillin@spock.usc.edu            *  for success"                  *
*661-718-0955 or 661-275-6795      *    -58th Rule of Acquisition   *

Relevant Pages

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