Ok, so what i got here is a drawing of a circuit. It's rectangular, with points a & b making up one side of the rectangle. It's a symetrical diagram-use your imagination...(adsbygoogle = window.adsbygoogle || []).push({});

7

4 __w__ 9

__w__| |__w__

| |__w__| |

| 18 |

| |

a b

The "w"'s are the resistors, and the number closest is it's resistance in ohms.

a) Find the equivalent resistance btw points a & b.

Easy. Add the resistance in parallel (1/R), then in series. I got 18.04 ohms.

b) If a potential difference of 34.0 V is applied between points a & b calculate the current in each resistor.

My main problem is I'm confused about the concept of "voltage drop". I know that the current is constant in series, but the voltage is not. That means by the time the current gets to the two resistors in parallel, the voltage is less that 34 V, right? How much less. Do you subtract the resistance of the first resistor (4 ohms) from the voltage-so the voltage entering the resistors in parallel is 30 V? Now voltage is the same in parallel- but also is the sum of the resistors? Hmmm, unless 25=30, I suspect an error in my thinking here...

Help!

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# Homework Help: Circuits: find current in the resistors

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