How do you find the total resistance of this parallel and series circuit? w/ solution please.?

Question

________________________
|***********|***********************|
+*******10 ohms**************10 ohms
10V*******|_____10 ohms____|
-***********|************************|
|********10 ohms*************10 ohms
|_______*|________________|

don't mind the stars, they're just space fillers.

Answer 1

Ok, from what I have understood of your graphic. There are two resistors in series, there are other two in series, and the one in the middel is in parallel.

Then : For the first two resistors, and the last two resistors :

Req = 10 + 10 = 20 ohms

Req = 10 + 10 = 20 ohms

So the Req for the first two and the last two are : 10 ohms and 10 ohms

those two, are in parallel with the one in the middel :

1 / R = 1 / 20 + 1 / 20 + 1 / 10

1 / R = 1 / 10 + 1 /10 = 2 / 10

R = 5 ohms

So the equivalent resistor will be : 5 ohms.

Answer 2

R = 1/(1/10 +1/10) + 10 + 1/(1/10 +1/10) = 5 +10 +5 = 20 ohms

Answer 3

Er, not the easiest diagram to interpret!
I take it that it is effectively a balanced bridge-type circuit with a 10v supply.

The trick is that the p.d. across the centre 10 ohm resistor is zero. Hence no current flows through it. If no current flows through it it might as well not be there as far as resistance calculations are concerned, since the current flow through the rest of the circuit will not be disturbed by its loss. Lose it.

The left hand pair of resistors can then be represented by an equivalent 20 ohm resistor, as can the right hand pair.

Two 20 ohm resistors in parallel gives you a total of 10 ohms.

Answer 4

Draw the circuit in paint, save to photobucket, post as link in questions. It's easy and you will get your circuit questions answered more easily and reliably. Plus us electronics guys, who want to answer your question, can stop pulling out hair out because people like you think they can get away with making a circuit diagram with asterisks, dashes, letters and numbers. IT DOESN'T WORK!