Current in a resistor and potential difference

AI Thread Summary
The discussion revolves around calculating the current in each resistor and the potential difference across a 200-ohm resistor in a given circuit. The user calculated the equivalent resistance (Req) as 12.22 ohms and found the current (I) to be -19.6 A, leading to a potential difference (deltaV) of -239 V. Concerns were raised about the accuracy of these calculations, suggesting a need for a better understanding of network theorems, including Kirchhoff's laws and source conversion methods. The user seeks clarification on whether their approach is correct or if adjustments are necessary. Understanding these concepts is essential for accurately solving the circuit problem.
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Homework Statement


In the circuit of figure p28.23, determine the current in each resistor and the potential difference across the 200 ohms resistor.

http://s848.photobucket.com/albums/ab41/tag16/?action=view&current=circuit.jpg&newest=1

Homework Equations



1/Req= 1/R1+1/R2+1/R3+1/R4
I=deltaV/R
deltaV= IR

The Attempt at a Solution



Req=1/(1/200ohms +1/80ohms+ 1/20ohms+ 1/70ohms)= 12.22 ohms

I=-240V/12.22ohms= -19.6 A
deltaV= (-19.6A)(12.22)= -239 V
Am I doing this completely wrong? If so what do I need to do?
 
Physics news on Phys.org
To solve this problem, you must know network theorems. Some of them are Kirchhoff law, source conversion method, etc.
 

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