Creating Circuits with equivalent resistances

[ragsz]

Homework Statement

Given 4 Identical resistors, I need to be able to find the 9 combinations of circuits with equivalent resistances

Homework Equations

Do I just keep flipping between parallel resistor sequences?

The Attempt at a Solution

I drew 3 different circuits that I believe to be correct, but cannot seem to come up with 9 different ones.

 

[berkeman]

Homework Statement

Given 4 Identical resistors, I need to be able to find the 9 combinations of circuits with equivalent resistances

Homework Equations

Do I just keep flipping between parallel resistor sequences?

The Attempt at a Solution

I drew 3 different circuits that I believe to be correct, but cannot seem to come up with 9 different ones.

Welcome to the PF.

Could you clarify the problem statement some? What do you mean by "equivalent resistances"? Equivalent to what? To one of the single R values? Or equivalent to some other value, and all 9 combinations are equivalent to that value?

 

[ragsz]

Maybe I should have typed it word for word... my bad. And thanks for the reply
You are given for identical 300 ohm resistors. Find as many ways of connecting all four resistors that give unique equivalent resistances. Then my professor gives us a hint that we should get 9 different arrangements using all four resistances that will give unique equivalent resistances.
Thanks

 

[berkeman]

Maybe I should have typed it word for word... my bad. And thanks for the reply
You are given for identical 300 ohm resistors. Find as many ways of connecting all four resistors that give unique equivalent resistances. Then my professor gives us a hint that we should get 9 different arrangements using all four resistances that will give unique equivalent resistances.
Thanks

Oh, unique equivalent resistances. So each configuration will result in a different equivalent resistance, and you have to use all 4 resistors in each configuration. Got it.

Show us what you have so far, and maybe we can offer some hints...

 

[berkeman]

I'm at 5 right now... Interesting problem.

 

[berkeman]

I'm at 5 right now... Interesting problem.

7...

 

[berkeman]

9.

How's it going on your end?

 

[ragsz]

Ok well here are my two... I know that's not much, but I think I am lost with this stuff.
http://imgur.com/ZyxobN4

 

[berkeman]

Ok well here are my two... I know that's not much, but I think I am lost with this stuff.
http://imgur.com/ZyxobN4

You probably don't have to draw the battery, just show the resistors with the connection points at the ends of the configuration. Unless the problem asks for you to show the battery for some reason.

So what you have shown so far is:

4R = R + R + R + R

R = R/2 + R/2

Now keep going. Try different combinations and connections, and see if they result in a different equivalent resistance. It's actually kind of fun...