NICE myv65!!! good points, lots of technical merit (you must've not gotten get sick of excel presentations like i did in school). i knew friction will eventually take mechanical energy out of the system (turning it in to heat), but literally speaking there is in fact a small % of energy going into maintaining a steady state fluid momentum whether or not it ends up being stored as air pressure (mostly for large air volumes), elastic energy (mostly tubing stretch), or lost as heat through friction. that includes just about all the energetic arguments for an h2o system: kinetic, potential, & losses (no radioactivity in or out, no electromagnetic energy created, which are good assumptions in this context).
we all should know the basics of energy conservation so well, energy in=energy out (at least at equilibrium, right?). i'm stoked about your experiment; it was extensive enough for us to claim that ~1/4 of the power will be picked up by the water. i'm not sure how useful that data is for other pumps, since the results will change with a different pump or if the pump has some degree of aircooling.
BTW,
EMI=interference is not a dominant issue here
HEAT=the result of dissipative loss (friction/resistance)
NOISE=vibration is kinetic energy (just oscillatory)
FRICTION=loss of mechanical energy to heat
perhaps we may more appropriately describe the energy system with:
EMF=electro-motive force (E&M field energy, sorry about the old jargon)
KE=kinetic energy (vibration, water movement...)
Dissipation=friction/resistance (both in the pump inefficiency & from the water path)
PE=potential/energy storage (pressure, hieght, capacitance, structural stress...)
n=coefficient of restitution (structural dissipation)
i'm no EE major, but i'm sure there are some momentum-like effects in electronics too (eddy-currents, inductance...?).
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