Electromagnetic Railgun - calculations

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The discussion focuses on calculating the speed limit of an electromagnetic railgun, which consists of two parallel rails and a metal bar moving between them in a vertical magnetic field. Participants explore relevant formulas, including the magnetic field equation B = μ₀I/(2πr) and the force equation F_max = Bvq. There is a suggestion to derive velocity using these formulas, leading to V = F_max/(μ₀Iq/(2πr)). One user expresses an interest in building a smaller version of the railgun, aiming for a muzzle velocity of 400-500 km/h, which they believe is achievable. The conversation emphasizes the theoretical calculations and practical aspirations related to railgun design.
paul-g
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Homework Statement



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.


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}}
 
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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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