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A Word About Vectors
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A Word About Vectors
It is important to recognize that each EKG electrode records only the
average
current flow at any given moment. Thus, although tiny swirls
of current may simultaneously be going off in every direction, each
lead records only the instantaneous average of these forces. In this
way, out of chaos, some very simple patterns emerge.
This concept is really quite simple; an analogy may be helpful.
During the course of a soccer match, a goalie may kick the ball many
different times to various members of his team (or, if our hypothetical
goalie is not very good, the other team). Some balls will go left, others
right, and still others straight down the field. However, by the end of
the game, the
average direction
of all of the goalie’s kicks and tosses
is likely to be straight ahead, toward the opposing net. This average
direction can be represented by a single arrow, or
vector
.
B
A
(
A
) The directions of each of the goalie’s kicks during the course of the
game. (
B
) A single vector represents the average direction and distance
of all of these kicks.