(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A circuit is constructed with five resistors and a battery as shown. The battery voltage is V = 12 V. The values for the resistors are: R1 = 54 Ω, R2 = 142 Ω, R3 = 148 Ω, and R4 = 109 Ω. The value for RX is unknown, but it is known that I4, the current that flows through resistor R4, is zero.

http://imgur.com/IwvnK

http://imgur.com/IwvnK

There is a picture of the circuit.

I know the current through R1 is 0.0594059406.

Here are my questions:

1) What is V2, the magnitude of the voltage across the resistor R2?

2)What is I2, the magnitude of the current that flows through the resistor R2?

3)What is RX, the value of the unknown resistor RX?

4)What is V1, the magnitude of the voltage across the resistor R1?

2. Relevant equations

I=V/R

3. The attempt at a solution

1) Essentially, I thought the voltage across V2 should be 12, the same as the battery because the voltage should be equal across parallel circuits. This answer is wrong, and I don't really understand why. I don't know how to use I=VR without knowing the current, which I know won't be the same and not knowing Rx.

2) I think I need the answer from 1 to do this one, and I can just use V=IR, but I don't know how to do it was Rx instead of a real number

3) Absolutely no idea.

4) I think this should be 12, but I don't think it is because of the first problem.

I am really having difficulty with this problem and would appreciate any help.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Circuit with Resistors and a Battery

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