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

Figure 27-33 (attatched) shows five 5.00 [tex]\Omega[/tex] resistors. (Hint: For each pair of points, imagine that a battery is connected across the pair.)

(a) Find the equivalent resistance between points F and H.

(b) Find the equivalent resistance between points F and G.

2. Relevant equations

For resistors in parallel:

[tex]R_{eq}=(\sum \frac{1}{R_i})^{-1}[/tex]

For resistors in series:

[tex]R_{eq}=\Sigma R_i[/tex]

3. The attempt at a solution

I solved part (a) by realizing that Resistors 1 and 2 are in series, Resistors 4 and 5 are in series, and both pairs are simultaneously in parallel with Resistor 3.

Thus:

[tex]R_{eq}=(\frac{1}{R+R}+\frac{1}{R+R}+\frac{1}{R})^{-1}[/tex]

[tex]R_{eq}=(\frac{1}{10}+\frac{1}{10}+\frac{1}{5})^{-1}=2.5[/tex]

So far, so good.

But for part (b), I can't come up with the correct combination. I said that Resistors 3 and 5 are in series, and they are in parallel with resistor 4. Resistors 1 and 2 are in series, but I don't see how they fit in with the rest of the circuit. I tried treating them as parallel to Resistors 3&5 and Resistor 4, and got 2.5 Ohm (wrong answer). I tried treating them as in series with Resistors 3&5 and then set all four of those resistors parallel to Resistor 4, and got 4 Ohm (still wrong).

Looking at it again, I just get more confused, because 1&2 join the circuit IN THE MIDDLE of the 3&5 series.

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# Homework Help: Equivalent Resistance in battery

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