Solving Resistor Circuits: Find Currents in R & 10Ω Resistors

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Homework Help Overview

The discussion revolves around a circuit problem involving resistors, specifically focusing on finding the currents in a resistor labeled R (19.1 Ω) and a 10 Ω resistor. The context includes the application of Kirchhoff's Laws and Ohm's Law.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to calculate the current through the 10 Ω resistor using the voltage drop across the resistor R. They express uncertainty about their approach after obtaining a voltage drop of 5.43204 V.
  • Some participants question the terminology used regarding voltage, clarifying the concept of voltage drop and suggesting further calculations to find the current through the 10 Ω resistor.
  • Others suggest using Kirchhoff's Voltage Law (KVL) to find additional voltage drops in the circuit to aid in determining the current.

Discussion Status

The discussion is active, with participants providing clarifications and suggesting methods to approach the problem. There is a focus on ensuring correct terminology and understanding of voltage drops, as well as exploring different paths to find the current in the circuit.

Contextual Notes

Participants are navigating the complexities of circuit analysis, including the implications of resistors in parallel and the need for accurate voltage measurements. There is an emphasis on the importance of understanding voltage drops at different points in the circuit.

Angie K.
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Homework Statement



P26_29.jpg
The resistor R in the above figure has a resistance of 19.1 Ω.

a. Find the current in the resistor R.

b. Find the current in the 10-Ω resistor.

2. Homework Equations


Kirchhoff's Laws (Junction Rule and Loop Rule)

V=IR

The Attempt at a Solution


I figured out part a (I got 0.2844 A) and got it right.
I am not sure how to go about finding the current of the 10 Ohm resistor.
I know current flows through the path of least resistance.

I tried finding the voltage of the resistor R (because I have the current and the Resistance) and that's 5.43204 V and then using that same voltage (because for resistors in parallel, the voltage is the same) to figure out the current of the 10 Ohm resistor. (5.43204V/10Ohms=.543204 A) Which is the wrong answer.

Someone please clarify where I need to go from the information that I already have.
 
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Be careful when you say "voltage of the resistor R". You actually mean the voltage drop (ie. voltage difference between the ends) is 5.43204. That means the other end (where the 10Ω is connected) is at 6 - 5.43204 = 0.56796V. You'll also need to find the voltage at the other end of the 10Ω to calculate the voltage drop, and only then can you calculate the current.
 
I meant the voltage drop. Sorry about that.

So that just gives me 5.43204 as the voltage drop of the other end and dividing by 10Ohms = .543204 Amps.
The one end has the voltage drop of .56796V and dividing that by 10Ohms , I get .056796 So now what do I do?
 
Angie K.-- use the KVL to find Voltage drop across the 2Ω resistor & then find the current through same. etc.
 
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