Potential difference between two points (VA - VB)

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The discussion focuses on calculating the voltage difference VA - VB in a circuit with a closed switch. The user applied the junction and loop rules to determine the currents I1 and I2, finding values of 0.161 A and 0.222 A, respectively, leading to a total current I3 of 0.383 A. The user calculated VA as 7.585 V and derived Vb through node C, resulting in a final voltage difference of 6.018 V. There is uncertainty regarding the accuracy of the calculations, and the user notes that related questions should remain in the existing thread. The thread is set to be deleted shortly.
johnknee
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Homework Statement


Q. With the switch closed, what is the voltage difference, VA-VB ?

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Homework Equations


Junction rule: I3 = I1 + I2
Loop rule(s)

The Attempt at a Solution


I solved for the currents in this circuit when the switch is closed.

Top loop(clockwise): +10V1 - 15*I1 - 47*I1 + (0V since I'm assuming no Voltage drop across switch) = 0
Bottom loop(counter clockwise): -5*I2 + 6V2 - 22*I2 + 0V = 0

For the top loop: I isolated I1 and got 10/62 = 0.161 = I1
For the bottom loop: I got 6/27 = 0.222A = I2
I1 + I2 = 0.161 + 0.222 = 0.383A.= I3

for the voltage difference VA - VB, I tried doing this with the guidance of a friend.
Va = 10 - I1*15 = 7.585 V.
Vb = Va - Vc - 6 (Vc being the voltage at node C where I3 flows through.)
Then Vc = Va - i1*47 = 7.585 - (7.567) = 0.018 V.
Vb = Va - Vc - 6 = 7.585 - 0.018 - 6 = 1.567 V.
Finally Va - Vb = 7.585 - 1.567 = 6.018 V

I am not sure whether I did this part correct.
 
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