Determine potential difference (circuits)

AI Thread Summary
The discussion focuses on determining the potential difference between points Va and Vb in a circuit. The user successfully calculated the current values and their directions but struggled to find the potential difference, expecting a result of 45V. Guidance was provided to choose a path from b to a and to account for potential changes across each resistor, noting that potential decreases in the direction of current flow. A participant confirmed the calculations, indicating that the result of approximately 45.38V was accurate. The conversation emphasizes the importance of applying circuit rules to find potential differences.
kyle
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Homework Statement



Va - Vb

reCeGVK.gif


Homework Equations



V = IR
Loop rule
Node rule

The Attempt at a Solution



I'm able to find each I value, as well as the direction of current. I'm not sure what to do after that. I know the answer should be 45V, but everything I've tried doesn't lead to that.
 
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Choose the zero of the potential at b. Knowing the currents on each resistor, choose a path leading from b to a, find the change of potential across each element. Note that the potential decreases in the direction of flow of a current.


ehild
 
45,3846V exactly, that is 590/13V
 
mr_pavlo said:
45,3846V exactly, that is 590/13V

It looks correct. :smile:

ehild
 

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