Electromagnetic Force Gun
How would I build an electromagnetic gun.
I need to know for a science project.
We want to propel a small metallic ball.
We wanted to test magnetic shielding by seeing how far
the ball is shot out of the electromagnetic gun.
I am not sure what this has to do with magnetic shielding.
Also, you will have to put the small metallic ball inside something
else that has a magnetic dipole (I think). Then the "gun" needs
to be made from alternating electromagnets that can change direction
to attract and repel the "bullet" as it passes down the barrel.
Hmmm. I am actually not too sure how this works - you probably should
look up articles in magazines like popular science - the other
name for this is a "railgun" - I am not sure why... Good luck!
If you want something a little simpler, you could try using a
solenoid from some relay mechanism. Take the core out of the solenoid so their
is room for your "bullet" and whatever shielding you plan to use
(if you need more room you could wind your own solenoid using a small
diameter wire with varnish insulation, wind it over a form that allows
your materials inside). The tricky part will be getting power to the
solenoid in some sort of reproducible way so that the ball always
is influenced by the magnetic field for the same amount of time, even
if the shielding affects the strength of the field. I would suggest
a light actuated sensor that "sees" when the ball goes into the
solenoid and shuts off the current.
This will not "shoot" the ball very hard but it might suffice for doing
the measurements you want to do. To make it quantitative you might try
"shooting" uthe ball up some sort of inclined surface and see how far up
it goes with different shielding in place. You could adjust the sensitivity
of your measurement by changing the slope of the ramp.
gregory r bradburn
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Update: June 2012