Electromotive Force: E=Vab=IR Explained

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SUMMARY

The discussion clarifies the relationship between electromotive force (emf) and potential difference in electrical circuits, specifically through the equation E = Vab = IR, where Vab represents the potential difference across a wire and I is the current. It emphasizes that the potential rise across an ideal source of emf is equal to the potential drop across the rest of the circuit, illustrating Kirchhoff's voltage law. This understanding is crucial for analyzing closed-loop circuits and determining current flow effectively.

PREREQUISITES
  • Understanding of Ohm's Law (V = IR)
  • Familiarity with Kirchhoff's Voltage Law
  • Basic knowledge of electrical circuits and components
  • Concept of electromotive force (emf)
NEXT STEPS
  • Study Kirchhoff's Voltage Law in detail
  • Explore practical applications of Ohm's Law in circuit design
  • Learn about ideal vs. real sources of emf
  • Investigate the impact of resistance on current flow in circuits
USEFUL FOR

Students of electrical engineering, circuit designers, and anyone seeking to deepen their understanding of electromotive force and circuit analysis.

AGGENGR
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The potential difference between the ends of a wire is given by Vab = IR. Combing that with E = Vab we have
E = Vab = IR (ideal source of emf).

" That is, when a positive charge flows around the circuit, the potential rise as it passes through the ideal source is numerically equal to the potential drop as it passes through the remainder of the circuit. Once and are known, this relationship determines the current in the circuit."- I can't seem to understand what this means?
 
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Imagine going around a closed loop in the circuit. As charge goes through the resistor it drops down in potential. As it goes through the battery it rises in potential. Those two potentials are equal in magnitude.
 
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...the potential rise as it passes through the ideal source is numerically equal to the potential drop as it passes through the remainder of the circuit.

If you think about it this is because the "ideal source" and the "remainder of the circuit" are connect to the same two nodes...
KVL.png


See also Kirchhoff's voltage law.
 
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Thanks i seem to get it after reading these posts and rereading the chapter! :):):):):):):):):):):):):):):):):):):)
 

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