Electric Circuit Analysis: How to find the sign for power?

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The discussion centers on the confusion surrounding the assignment of signs for power in electric circuit analysis, particularly the lack of clarity in textbooks regarding active and passive sign conventions. It questions the rationale behind memorizing signs based on current direction instead of using a more intuitive method that considers voltage and current relationships. The suggestion to refer to Valkenburg's work over Boylested's indicates a preference for clearer explanations. The need for a more straightforward approach to understanding power signs is emphasized. Overall, the conversation highlights the challenges faced by students in grasping these fundamental concepts.
tahayassen
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My textbook does a very poor job of explaining how to assign signs to power: http://www.mediafire.com/view/?e0xr8j41tokujx6

It goes on to explain passive sign convention but it never explains active sign convention. Also, shouldn't the sign for power depend on voltage and current since power is just voltage times current? Why does it essentially tell me to memorize the signs depending on the direction of the current? Surely there is a more intuitive approach?
 
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Read Valkenburg instead of Boylested.
 
Kholdstare said:
Read Valkenburg instead of Boylested.

I have no idea to what you're referring to.
 
I am trying to understand how transferring electric from the powerplant to my house is more effective using high voltage. The suggested explanation that the current is equal to the power supply divided by the voltage, and hence higher voltage leads to lower current and as a result to a lower power loss on the conductives is very confusing me. I know that the current is determined by the voltage and the resistance, and not by a power capability - which defines a limit to the allowable...

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