In a message dated 2/7/03 7:19:57 PM Eastern Standard Time,
MorgusMagnificen@aol.com writes:
> Let's calculate (not speculate) on the (Lorenz)force acting on a welding
> cable laying at ground 0, and one-meter long, carrying a current of
> 1000A.,
> due to its interaction with the geomagnetic field, which we will assume to
> be
> vertical and of magnitude B=1Gauss (good estimates - just ask your friendly
>
> geophysicist). Of course, we all recall that the formula for the force on a
>
> straight conductor in a B-field is:
>
> F=BxLxI (MKS units)
>
> Using MKS units: F=.00001 x 1 x 1000=.01N.=.0022Lbs=.032Oz.
> Should really shake up that 4/0! Remember - this is the total force on
> 1METER of cable, with 1000AMPS flowing.
>
> Eric von Valtier K8LV
>
Eric,
You can speculate all you want and by plugging numbers into formula,
get almost any number you want by making assumptions. Lets look at the real
world of results.
I worked in a basic research labortory where we used a pulsed
solenoidal DC magnet which generated such a strong field that it had to be
cooled by liquid nitrogen before it was activated so that it would not
destroy itself. The conductors carrying current to the magnet had to be
restrained by heavy wooden boards to prevent them from moving. The field
outside the magnet was so strong that it picked up a pair of scissors which
were inadvertantly left laying on a work bench 10 feet away and buried them
in the wooden shroud surrounding the magnet. The scissors ended up on a
radius of the axis of the magnet.
No small force here.
73 de
Dave, WT8R
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