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more physics (short)



Sorry I was doing a bit more physics calculations for the Web pages and ran
into a problem.  So if you can verify my new numbers vs the old ones I'ld
appreciate it.

Kelly


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Using the old equation p=1/2 M V^2  we get the
power (in watts) = 1/2 Mass (in Kg) * (exaust velocity in meters/sec)^2

Given the fuel numbers show watts per Kg the equation shuffels around to:

Exaust velocity (in Meters per secound) =sqrt (2 * Power)

>> Did I mess this up?  Yes I'm ignoring relativistic <<


Fuel --> Exhaust        Watts /
                        kg

p + 11B --> 3 4He       6.926 E13      11,800,000 m/s
De + 3He --> 4He + p    3.505 E14      26,500,000 m/s
                                                                            *
6Li + 6Li --> 3 4He
 (Combined)             1.596 E14      17,800,000 m/s
                                                                            **
 3He + 3He --> 4He + 2 p
                        2.059 E14       20,300,000 M/s
                                                                            ***


This all seems pretty straight forward, but then I noticed we had
previously come up with exaust velopcities of:


================================================================
Fuel type                   Exhaust speed            Specific Impulse
                                                                    (Isp)
p + 11B --> 3 4He          14,000,000 M/sec     1,400,000.  seconds

De + 3He --> 4He + p

 6Li + 6Li --> 3 4He       21,000,000 M/sec     2,100,000.  seconds

 3He + 3He --> 4He + 2 p   24,000,000 M/sec     2,400,000.  seconds




So which numbers are corect, the first group or secound?

Kelly


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Kelly Starks                       Internet: kgstar@most.fw.hac.com
Sr. Systems Engineer
Magnavox Electronic Systems Company
(Magnavox URL: http://www.fw.hac.com/external.html)

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