#### subatomic particle

Joined May 8, 2018
76
how can this happen?

how could we delete the resistance on the left?
Can anyone explain?

Thanks

#### AlbertHall

Joined Jun 4, 2014
12,384
What is the voltage across that resistor?

#### subatomic particle

Joined May 8, 2018
76
What is the voltage across that resistor?
Well i dont know, but i think it doesnt matter.
I am learning how to semplify symmetrical circuits, and in the example i posted above the voltage was not mentioned.

#### MrChips

Joined Oct 2, 2009
30,925
Well i dont know, but i think it doesnt matter.
I am learning how to semplify symmetrical circuits, and in the example i posted above the voltage was not mentioned.
The question "What is the voltage across that resistor?" was meant for you to think about the problem and the answer.
It does matter. In the example posted, you do not need to be given the voltage. You need to determine this on your own.
Try to determine the voltage across that resistor and that will lead you to the answer to your original question.

#### KeithWalker

Joined Jul 10, 2017
3,135
how can this happen?
View attachment 172582

how could we delete the resistance on the left?
Can anyone explain?

Thanks
You could use an eraser or white-out. You don't define what the result of deleting it should be.

#### subatomic particle

Joined May 8, 2018
76
The question "What is the voltage across that resistor?" was meant for you to think about the problem and the answer.
It does matter. In the example posted, you do not need to be given the voltage. You need to determine this on your own.
Try to determine the voltage across that resistor and that will lead you to the answer to your original question.
Oh i understand!! The voltage is 0V because C and D have the same potential thats why we can remove it
Thanks so much!

#### shteii01

Joined Feb 19, 2010
4,644
how can this happen?

how could we delete the resistance on the left?
Can anyone explain?

Thanks
Where is this educational material coming from?

#### mvas

Joined Jun 19, 2017
539
Oh i understand!! The voltage is 0V because C and D have the same potential thats why we can remove it
Thanks so much!
Yep, the clue was the word "symmetrical", that appears in the title of your thread.

#### shteii01

Joined Feb 19, 2010
4,644
Overall. The 3 resistors in the middle form a Y. Transformation from Y to Delta is well known technique. It is a bit cumbersome to do, but you can probably program your graphing calculator to do it for you. Therefore, the whole thing that you want us to explain is a waste of time. This sort of exercise asks student to reduce The Whole Network of resistors to just one equivalent resistor. So how you do the middle part does not matter.