R: formula needed

[Raoul Raffagli]

Yes, I know, it's true, but I think a magnetic camp is the best way to solve
my problem. Need to attract a very light metallic plate at about 1 cm. I
think it's no good to make a magnet that needs a kW to do this, so instead o
"trying" with high power I should calculate the right geometry and the
energy required. It's quite a difficult problem, I know, but it's very
important; instead of attracting it, it would be good too if i cuold push
very fast, and the fastness must be controlled by current. I thougt of a
air-pressured system (electronically driven), but doesn't seem so good
'cause it would make too much noise. MMMhhh, I must work a lot to solve it.
Thanks,
    Raoul

----- Original Message -----
From: Paul Perry <pfperry at melbpc.org.au>
To: Raoul Raffagli <Raffa_Raoul at iol.it>
Sent: Thursday, August 10, 2000 2:36 AM
Subject: Re: formula needed


> At 10:30 PM 9/08/00 +0200, you wrote:
> >Hi all. Planning a new project that includes also mechanical parts
> >electrically driven. I need to calculate what kind of electro-magnet I
must
> >use and what current does it need to attract a metallic plate at a
certain
> >distance with a determinate force.
>
> The shape of the plate, the geometry of the magnet make a difference.
> It is very difficult to attract anything at a distance, because the
> power falls off as an inverse square approximately.
> You will get a good idea by experimenting with a permanent magnet.
>
> paul perry Melbourne Australia
>
>