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# minds gone blank - electrical energy equations watch

1. I know im a silly sausage, but I forgot the electricl energy equations. Well not neccesarily... I specificaly cannot think of any that do not have time as a variable. Any help?
2. erm lemme think, P=IV, therefore energy = Pt = IVt
but Q=It, therefore t=Q/I

therefore energy = QV, E=QV ( i think thats one then? lol)
3. but Q=It, thus dependant on time
4. Indirectly dependent I guess, but if you use E=QV, you don't need a value for time

That equation itself is independent of time

Sorry I'll try and think of other equations! What exactly is it that you are trying to do?

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I'm not sure there's any other way of defining electrical energy??
5. well, mwasure the efficiency of a motor. Id like to avoid having to measure the time in which the system is on though.
6. Yeah well if you use E=QV

then you just need to measure the Charge (Q) and the Voltage (V), not time!
7. but Q=It, unless you have a means of measuring charge without measuring time?
8. Coulomb meter? multimeter?
9. multimeters measure charge?! SWEET!. Cheers
10. yep most do!

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Updated: November 19, 2005
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