Understanding the Passive Sign Convention for Electrical Engineers

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SUMMARY

The discussion focuses on the Passive Sign Convention in electrical engineering, which dictates that current enters the positive terminal of a passive device and exits from the negative terminal. Voltage drop indicates a decrease in voltage from a higher positive value to a lower one. When analyzing circuits, selecting a positive terminal and current direction is crucial; a negative result indicates an incorrect assumption about the current's direction. Clarity in problem statements is essential, particularly regarding voltage and current directions.

PREREQUISITES
  • Understanding of electrical circuit analysis
  • Familiarity with voltage and current concepts
  • Knowledge of passive components in circuits
  • Experience with using voltmeters and ammeters
NEXT STEPS
  • Study the Passive Sign Convention in detail
  • Learn how to analyze circuits using Kirchhoff's laws
  • Explore techniques for measuring voltage and current accurately
  • Review common passive components and their characteristics
USEFUL FOR

Electrical engineering students, circuit designers, and professionals involved in circuit analysis and measurement techniques will benefit from this discussion.

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Homework Statement
Please help. I've tried understanding why the values are what they are but I keep getting confused. Can I get a detailed and clear instruction simple enough for a potato to understand.
I understand that both currents are negative because the current to 1 is positive but even then, I need help.
Relevant Equations
I don't know if any equations are involved to make it more understandable
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What exactly is your question? Voltage drop implies the voltage has decreased, from a higher value positive to a lower positive. The convention is that current enters into the positive side (higher positive voltage) of a passive device and exits from the negative terminal.

When analyzing an unknow circuit, you often choose a convention (pick a positive terminal and a current direction). Sometimes you get a negative number, which means that you guessed wrong. But not to worry, it just means it is in the opposite direction.

The wording in the problem statement seems a little vague to me, though. They say voltage drop between 1 and 2, but on one of them terminal 1 is positive, the other has terminal 2 positive. To me, that suggests putting the positive lead of a voltmeter on the one labeled (+). Then they say "current entering terminal 1, but then the arrow may be different. My guess is that you hook up an ammeter in such a way that you're expecting a positive number based on the arrow. If you can, try to ask your instructor for clarity as to what you are answering.
 
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