Re: railguns

On 15-Sep-99 at 16:44, Oerjan Ohlson (oerjan.ohlson@telia.com) wrote:
> Los wrote:
> 
> > A question for you propellor heads. At what velocity do you think a
> decent
> > railgun projector (ala KV design) would spit out its slugs and how
> large
> > would they be?
> 
> It depends on the precision in your targetting sensors, the size of
the
> target and the ranges you want to hit at. Assuming the "standard FT
> scales" and shotgun-style fire with several (preferrably *lots* of)
> projectiles into the target volume each time you fire, aiming to
> achieve the MT railgun hit probabilites, 3000 km/s (0.01c) might be
> sufficient... How to achieve such velocities is another matter
> entirely, but who knows what tech will be available in the future?
> 
> At those speeds, the slugs don't need to be very large - the kinetic
> energy of a 10-gram slug travelling at 0.01c is IIRC about one kTon,
> but don't quote me on that yet since my reference books are at work
:-(

1kTon tnt = 6.31*(10**8)joules	(newton*meter)

My (probably faulty, if someone could check) old physics says it works
out to about 1kTon being about the same as 10 grams at 355km/sec 
relative velocity.  Hmmmm, about .001c.

Roger