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

In summary, the conversation discusses the inadequacy of a textbook's explanation of assigning signs to power. The speaker questions the use of passive sign convention and the lack of explanation for active sign convention. They also suggest reading Valkenburg instead of Boylested for a more intuitive approach.
  • #1
tahayassen
270
1
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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  • #2
Read Valkenburg instead of Boylested.
 
  • #3
Kholdstare said:
Read Valkenburg instead of Boylested.

I have no idea to what you're referring to.
 

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

What is electric circuit analysis?

Electric circuit analysis is a branch of electrical engineering that deals with the study and analysis of electrical circuits. It involves the use of mathematical methods and techniques to understand and analyze the behavior of electric circuits.

What is the sign for power in electric circuit analysis?

The sign for power in electric circuit analysis depends on the direction of current flow and the polarity of the voltage source. If the current flows in the same direction as the voltage source, the power is positive. If the current flows in the opposite direction, the power is negative.

How do you find the sign for power in an electric circuit?

To find the sign for power in an electric circuit, you need to determine the direction of current flow and the polarity of the voltage source. Then, use the formula P=IV, where P is power, I is current, and V is voltage. If the values for I and V have the same sign, the power is positive. If they have opposite signs, the power is negative.

Why is it important to know the sign for power in electric circuit analysis?

Knowing the sign for power in electric circuit analysis is important because it helps us understand the behavior of the circuit. A positive power indicates that energy is being supplied to the circuit, while a negative power indicates that energy is being dissipated from the circuit. This information is crucial for designing and troubleshooting electrical systems.

Can the sign for power change in an electric circuit?

Yes, the sign for power can change in an electric circuit. This can happen when the direction of current flow or the polarity of the voltage source changes. It is important to keep track of these changes to correctly analyze and understand the behavior of the circuit.

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