Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!henry
From: henry@utzoo.UUCP (Henry Spencer)
Newsgroups: net.space
Subject: Re: homemade railguns...
Message-ID: <6308@utzoo.UUCP>
Date: Tue, 21-Jan-86 16:02:30 EST
Article-I.D.: utzoo.6308
Posted: Tue Jan 21 16:02:30 1986
Date-Received: Tue, 21-Jan-86 16:02:30 EST
References: <8601171419.AA20243@s1-b.arpa>, <2611@amdahl.UUCP>
Organization: U of Toronto Zoology
Lines: 19

> It was my understanding that rail guns took a fractional second
> to a few seconds to accelerate something depending on design.
> Surely a model could be built that would be able to use computer
> grade caps?

But the output velocity probably wouldn't be too hot, not from a gun
of practical length.  Assuming a constant acceleration, v^2 = 2ad,
which translates as "to get a high velocity, you need either a high
acceleration (short transit time, high currents, low-inductance caps)
or a very long gun (gets physically cumbersome very quickly)".  The
problems of gun length are why rail-gun and mass-driver work tends to
push for very high accelerations.  Phrased another way, again for a
constant acceleration, v = 2d/t, which means that a velocity of hundreds
of meters per second (a high-velocity rifle is maybe a thousand) means
acceleration times of a few milliseconds if the gun is to fit in an
average-sized room.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry