Cecil Moore wrote:

For engineers, the direction of the arrow for the Power
Flow Vector in joules/sec is generally accepted to be the
same as the direction of the joules.

I am an engineer, Cecil. I just happen to work in the field of physics.
I could be wrong, but I don't think a Bird wattmeter measures or
displays Power Flow Vector.

From the IEEE Dictionary: "power-flow vector - Vector-
characterizing energy propagation caused by a wave and
giving magnitude and direction of power per unit-area
propagating in the wave."


Please note the "*DIRECTION OF POWER* ... *PROPAGATING*
in the wave", a direct contradiction to your above assertion.

The power measured at the source somehow finds its way to the
load in spite of not having any direction (according to you. :-)

Well, it's true for me and probably for most other people who have a
grasp of the subject. It's actually energy which does the moving.
Power is just the rate at which energy finds its way there.

It's like this. Let's say you're riding your Harley through town at 50
MPH and somebody pulls out of a side street right in front of you. Does
the speed of your motorcycle collide with the car, or does your
motorcycle collide with it?

73, ac6xg