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

In Figure 27-72, an ideal battery with an emf of = 14.0 V is connected to a network of resistances with R1 = 7.00 , R2 = 12.0 , R3 = 4.00 , R4 = 1.00 and R5 = 6.00 . What is the potential difference across R5?

FIGURE:

|----**R1**---|

| |---**R3**---|

|---**R2**----| |

| |--|

| | |

|---**R4**-------**R5**----| |

| | |

|-----------+\emf\-----------|--|

2. Relevant equations

V=iR

Parallel R = R12 = (1/R1 + 1/R2)^-1

Series R = R12 = R1 + R2

3. The attempt at a solution

I just typed a realllllly long attempt at my solution and the page crashed and I lost everything, and I'm at work...so briefly:

R1 and R2 are parallel so R12 = (1/7 + 1/12)^-1 = 4.42ohm

R12 and R3 are in Series so R123 = 4.42ohm + 4ohm = 8.42 ohm

R4 and R5 are in Series so the same = R45 = 7ohm

R123 and R45 are parallel so R12345 = (1/8.42 + 1/7)^-1 = 3.822 ohm

after attempting various things involving V = iR (where R's in Series have same i and R's parallel have same V) I cannot seem to get the potential difference across R5...PLEASE HELPPPPPP

thanks so much

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# Homework Help: Potential Difference with Series and Parallel Resistors

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