Potential difference calculation

Thread starter ellieee
Start date May 10, 2021
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Calculation Difference Potential Potential difference

AI Thread Summary

In potential difference calculations, a wire is treated as 'perfect,' meaning the potential is uniform along its length. Consequently, when two resistors are connected by a wire, the ends of the resistors are at the same potential. This principle is crucial for solving school problems related to electrical circuits. Understanding this concept ensures accurate calculations of potential differences across components. Accurate application of these principles is essential for mastering circuit analysis.

May 10, 2021

ellieee

Homework Statement: for the 2 resistors in parallel, is is true that only need to find p.d across one of them (eg. (5.0)(1.0)=5.0V) to determine the p.d across both parallel resistors ? in this case (2.0.)(2.5) = (5.0)(1.0), but what If the p.d across resistor A not equal to that of B, then which resistor do you calculate the p.d of?

Relevant Equations: V=IR

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May 11, 2021

Orodruin

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That cannot happen.

May 11, 2021

Tom.G

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For these types of school problems, a wire is considered to be 'perfect'; specifically that is: "The potential at any point on a wire is the same as the potential at any other point on that wire."

Keeping that in mind, since the respective ends of the two resistors A and B are connected by wire, they are at exactly the same potential.

Hope this helps!

Cheers,
Tom

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