Potential difference calculation

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ellieee
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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
Circuit schematic with a two-cell battery, a voltmeter across the battery, a 1.0 Ω resistor in series, and two parallel branches: branch A with a 1.0 Ω resistor carrying 5.0 A, and branch B with a 2.5 Ω resistor carrying 2.0 A, handwritten labels A and B.
 
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  • Circuit schematic with a two-cell battery, a voltmeter across the battery, a 1.0 Ω resistor in the main branch, and two parallel branches: branch A with a 1.0 Ω resistor carrying 5.0 A, and branch B with a 2.5 Ω resistor carrying 2.0 A.
    CamScanner 05-11-2021 12.11_2_edit_8520459510157.jpg
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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