How to Find the Reading of Voltmeters in a Circuit with Identical Resistors?

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The discussion centers on calculating the readings of voltmeters in a circuit with identical resistors and a given voltage. Initial attempts at solving the problem involved applying Kirchhoff's Law, but incorrect calculations for current were noted, with confusion over the total current and branch currents. After clarifying the current values, the correct readings were proposed as V1=V2=V/9 and V3=2V/9. However, there was disagreement, with one participant suggesting that V1 and V2 should read 0 and V3 should read V/3 instead. The conversation highlights the importance of accurate current calculations in circuit analysis.
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Homework Statement


In the circuit shown below, all three voltmeters are ideal and identical. Each resistor has the same given resistance R. Voltage V is also given. Find the reading of each voltmeter.


The Attempt at a Solution



i = 2V/3R
Applying Kirchhoff's Law to BACDE
V1+V2=0

Loop CDHFG
V1+V3=2V/3

Loop DEH
V2+V3=2V/3

Solving these three, I get incorrect answers.
 

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You've calculated I incorrectly. Since the voltage V appears across 3 R's in series, I = V/(3R).
 
phyzguy said:
You've calculated I incorrectly. Since the voltage V appears across 3 R's in series, I = V/(3R).

Oops! I used incorrect notation for current. The current in the circuit as a whole is 2V/3R. The currrents in individual branches are V/3R.
 
utkarshakash said:
Oops! I used incorrect notation for current. The current in the circuit as a whole is 2V/3R. The currrents in individual branches are V/3R.

Correct. Does this solve your original problem?
 
phyzguy said:
Correct. Does this solve your original problem?

No. The correct answers are V1=V2=V/9 and V3=2V/9
 
utkarshakash said:
No. The correct answers are V1=V2=V/9 and V3=2V/9

If you've posted the problem correctly, I don't think that can be the correct answer. VC = VE = V/3, so V1 and V2 should both read 0 and V3 should read V/3.
 
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