@S1-A.ARPA,@MIT-MC.ARPA:Smith@UDel-Dewey.ARPA (07/11/85)
From: Smith@UDel-Dewey.ARPA
Hi all!
Since this is my first time here I should introduce myself... My name is
art smith, and I am a recent graduate of the University of Delaware with
Master's degrees in Chemistry and Computr Science. I've been reading this
bboard for a while and two recent entries prompted me two respond...
First: cancelling angular momentum with angular momentum is QUITE
different from cancelling mass with mass -- one is a vector quantity, and
the other a scalar. The real difficulty (pardon the pun) is that the
various vectors of angular momentum don't have the same base point, and
so cancelling can be difficult. Just 'cause the vectors are equal in
magnitude and opposite in direction doesn't mean they exactly cancel --
they may produce a torque, as in:
<-------+ <-force vector one
| This arm will turn.
+ <-pivot on arm
|
+-------> <-force vector two
Secondly: The idea of tapping the potential difference in the solar
wind at the leading and trailing edges of the earth by "stretching a cable
from one side of the field to the other" may have problems besides the
obvious (and NO FUN) logistic ones... It assumes (at least) that the
cable has a lower resistance than the plasma which has been elsewhere
described as very conductive. Just because there is a potential difference
at two ends of a (sufficiently long and narrow) cable does NOT mean that
a current will flow. It may be a very stable potential gradient caused
by external conditions. Does anyone who understands these things better
than I (i.e. most of you) have any feelings on this?
Hope to be contributing more...
art smith
(smith@dewey.ARPA)
(302) 451-6337 <- can leave a message, at least!