The Potential Difference between 2 points

AI Thread Summary
The discussion centers on calculating the potential difference between two points in a circuit diagram. The user has determined the currents I1, I2, and I3 but is struggling to find the correct potential difference. They initially calculated a value of 1.15 V using the formula (0.30*5) - 0.35, which they believe is incorrect. Other participants inquire about the reasoning behind the user's calculations and the meaning of the expression used. Clarification on the methodology and correct application of circuit principles is sought to arrive at the accurate potential difference.
simion
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Homework Statement


What is the potential difference between points a and b in the diagram?
http://imgur.com/Ubr4A


Homework Equations





The Attempt at a Solution


I have calculated the currents to be:
I1=0.30A
I2=0.65A
I3=0.35A
What I tried doing was (0.30*5) - 0.35= 1.15 V but it's not right. Any help?
 
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What is the value of V1?
http://img820.imageshack.us/img820/5158/cctb.jpg
 
Last edited by a moderator:
Sorry, it's 12.0 V
 
simion said:

Homework Statement


What is the potential difference between points a and b in the diagram?
http://imgur.com/Ubr4A


Homework Equations





The Attempt at a Solution


I have calculated the currents to be:
I1=0.30A
I2=0.65A
I3=0.35A
What I tried doing was (0.30*5) - 0.35= 1.15 V but it's not right. Any help?

How did you arrive at that last expression? What does it represent?
 
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