Finding resistance between two ends with series and parallel resistors

[Aditya3003]

Homework Statement

I need to find to resistance and am having problem as I do not know KCL's. All I know is the total resistance in series or parallel. I have attached the image. Find resistance b/w the 2 ends.

Homework Equations

If you have Resnik & Halliday open page 723(Vol2). and see figure 31-41. My question is same with r = 20ohm & R=10ohm.

The Attempt at a Solution

 

[gneill]

Homework Statement

I need to find to resistance and am having problem as I do not know KCL's. All I know is the total resistance in series or parallel. I have attached the image. Find resistance b/w the 2 ends.

Homework Equations

If you have Resnik & Halliday open page 723(Vol2). and see figure 31-41. My question is same with r = 20ohm & R=10ohm.

If you don't know the basic circuit laws it's going to be difficult to proceed; All you can do is try to apply "canned" formulas. Hint: Look up "Y-Delta transformation".

 

[mfb]

One resistor has zero current inside due to symmetry, you can remove it and use your formulas for resistors in series/parallel afterwards.