I am trying to make a small iron cylinder (quarter of inch diameter ) propel out of a small pipe (PVC?) I am trying to use electromagnetic forces to do this, I.E. solenoid. How can I make it most efficient, more turns of wire? closer distance from turns of wire? how much voltage and current will I need?
It depends how far and how fast you intend to propel the iron cylinder. (It also depends whether that cylinder is magnetic, and how much friction you need to overcome, and how long it is, and so on.) What are you trying to achieve?
its for a demonstration the cylinder would not be more than half a inch.it would be iron so would not be magnetic.I would like to propel it around 50 feet. I was thinking ultra-capacitors to charge and release the electricity all at once. what do I need to do to make this work?
Do some simple ballistics calculations (you can assume vacuum if it makes things easier) - it should be fairly simple to come up with the minimum energy requirements.
Since the iron cylinder is not magnetic, all the solenoid will do is attract it. It would take some pretty clever timing to collapse the magnetic field when the cylinder was moving at the desired speed so that it turned into a projectile and carried out through the far side of the solenoid. Not saying it's impossible, but it doesn't seem very easy to me. Is it important that the cylinder itself is the projectile? If you use the solenoid as an impulse driver to throw something else, the problem gets much easier.