Determining values of resistance, voltage, and current throught a circuit

AI Thread Summary
The discussion revolves around solving a circuit problem involving total resistance, current, and voltage using Kirchhoff's loop rule and Ohm's law (V=IR). A participant expresses confusion regarding the interpretation of current and voltage values, particularly the significance of the 1.5A current and the polarity of the battery terminals. Clarifications are provided about the battery's positive and negative terminals, as well as the flow of current in the circuit. The conversation highlights the importance of marking currents, identifying potential differences, and using Kirchhoff's rules to set up equations for solving circuit problems. Ultimately, the participant resolves their query about calculating resistance using the formula V=IR.
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Homework Statement



Question asks for a lot of stuff...
Total Resistance
Total Current
R1, V1 <
V2, I2 <----- R=resistance V=Voltage I= Current 1 is resistor 1, 2 is res2...
R3, I3 <

Homework Equations



V=IR
Kirchoffs loop rule

The Attempt at a Solution



Well I am completely lost because i don't know a few things.
well to start it off, I am going to have to use the loop rule. here's my few questions before i actually start it. Where it says the 1.5A after R1, does that show that the amplitude for R1 is 1.5 or the amplitude for the parallel circuit after it is 1.5A. for the V on the top, how do i know which is positive and which is negative (doesnt have long and short lines). and with the 9v battery, it has 2 sets of small lines and big lines. does this mean anything or is it just left is - and right is +?
 

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Firstly, with the battery the smaller line (on the left) is negative, the other is positive. You should be able to work out which side of the V is negative and which is positive from that. The A is just showing that there is 1.5amps flowing through the circuit at that point. That's the best i can do for now so if anyone else has more detail, please add.
 
Hints on solving circuit problems in the steady state (i.e., \frac{\partial \Phi_B}{\partial t} = 0):

  1. Mark the different currents
  2. Identify the potential differences across batteries, resistors, and capacitors (for the latter, assign arbitrary charges)
  3. Identify the loops you will evaluate
  4. Use ΔV =0 to find equations for potential difference
  5. If needed, use Kirchhoff's junction rule to find the relationship between currents
  6. Solve the system of equations
 
frog210293 said:
Firstly, with the battery the smaller line (on the left) is negative, the other is positive. You should be able to work out which side of the V is negative and which is positive from that. The A is just showing that there is 1.5amps flowing through the circuit at that point. That's the best i can do for now so if anyone else has more detail, please add.

like what I am trying to ask is if you do V=IR would it be 9V=1.5A*R1 and then you could find r1 like that?
 
nevermind, i found it out. thanks for the help
 
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