# Homework Help: Electromagnetic Railgun - calculations

1. Oct 14, 2011

### paul-g

1. The problem statement, all variables and given/known data

Electromagnetic Railgun consists of two parallel, distant from the horizontal, very long rails, after which moves perpendicular to the rails, linking them to the metal bar of mass m.

The rails are in a vertical magnetic field intensity B. What is the speed limit the beam, if the voltage is connected to the rails U. Skip the resistance to motion of the beam.

3. The attempt at a solution

May i use
$B=\frac{\mu_{o}I}{2\pi r}$

Which formula combined to calculate the velocity?

Maybe:
$F_{max}=Bvq$

$F_{max}=\frac{\mu_{o}I}{2\pi r}vq$

$V=\frac{F_{max}}{\frac{\mu_{o}Iq}{2\pi r}}$

2. Dec 15, 2011

### Fr1ki

Try this site, seems very legit.
http://www.powerlabs.org/railgun2.htm
Im trying to build one myself, but much smaller than the one in the link. Thinking 400-500 km/h muzzle velocity. seems very achievable
Good luck hope this helped

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