- #1

- 11

- 0

## Homework Statement

(this wasn't the original problem, but a part of it, but I got this part wrong)

Find the R equivalent of the circuit

http://img508.imageshack.us/img508/2191/circuitam6.jpg [Broken]

## Homework Equations

(parallel) 1/Req = 1/R1 + 1/R2 + 1/R3 + ...

(series) Req = R1 + R2 + R3 + ...

## The Attempt at a Solution

My teacher gave back the paper, and I got it wrong, but I still don't understand why mine is wrong and his is the right way to do it.

1. I took the 10-ohm and 50-ohm in parallel, and got 8.33-ohm as equivalent.

2. (this is where the mistake occurred) I took the 20 ohm and 40ohm in series, so it'll be 60-ohm equivalent.

3. Then I took the 60-ohm and 8.33-ohm and put them in parallel, but that's wrong, but I don't understand why that's wrong. How would I know that I would have to put the 20ohm and 8.33 ohm in series, then parallel with the 40ohm INSTEAD of doing the way I did it?

Please help, thanks

Last edited by a moderator: