How to calculate projectile velocity in a magnetic railgun

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Hey everyone

I've been wanting to create a magnetic railgun for some time. I have a few questions though.

1. What equations can i use to calculate how fast the "projectile" are moving?
2. Why do the magnets respond like this when electricity flows??

Thanks!

 

[berkeman]

The wikipedia article will get you started:

http://en.wikipedia.org/wiki/Rail_gun

 

[Crosson]

2. Why do the magnets respond like this when electricity flows??

The answer is that electricity and magnetism are the same force, seen from different points of view.