Current in a resistor and potential difference

[tag16]

Homework Statement

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

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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?

 

[rl.bhat]

To solve this problem, you must know network theorems. Some of them are Kirchhoff law, source conversion method, etc.

 

[tomcue]

I appreciate your attempt to solve this circuit problem using the equations for equivalent resistance and Ohm's law. However, your calculations seem to be incorrect.

Firstly, the equivalent resistance formula you used is for resistors in parallel, but the resistors in this circuit are in series. The correct formula for equivalent resistance in series is simply the sum of the individual resistors, so the equivalent resistance in this case is 200 ohms + 80 ohms + 20 ohms + 70 ohms = 370 ohms.

Next, to calculate the current through each resistor, you can use Ohm's law (I = V/R). The potential difference (V) across the 200 ohms resistor is given as -240V, and the equivalent resistance is 370 ohms. Therefore, the current through the 200 ohms resistor is -240V / 370 ohms = -0.65A.

Similarly, you can calculate the current through the other resistors by using the same formula with the appropriate potential difference and resistance values.

I hope this helps clarify the correct approach to solving this circuit problem. Keep up the good work!