Difficult : Calculate equivalent resistance of the circuit problem .

AI Thread Summary
The discussion revolves around calculating the equivalent resistance between points A and D in a circuit with all resistors valued at 1 ohm. Initial attempts to simplify the circuit included identifying two resistors in parallel, but this was deemed incorrect. Participants suggested removing open circuit resistors and redrawing the circuit for clarity, leading to a realization of two pairs of resistors in series. The final calculations indicated that the equivalent resistance could be calculated as 1.75 ohms, but there was confusion regarding the accuracy of this result. The thread concludes with a recommendation to show detailed work or start a new thread due to the age of the discussion.
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Homework Statement



Calculate the total equivalent resistance between A and D -
r8ibJ.png

( All resistors are 1 ohm )

Homework Equations


-


The Attempt at a Solution


The only thing I can see is that the two straight 1 ohm resistors are in parallel , giving 1*1/1+1= 1/2 resistance. But what next , please help !
 
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agoogler said:

Homework Statement



Calculate the total equivalent resistance between A and D -
r8ibJ.png

( All resistors are 1 ohm )

Homework Equations


-


The Attempt at a Solution


The only thing I can see is that the two straight 1 ohm resistors are in parallel , giving 1*1/1+1= 1/2 resistance. But what next , please help !

It's not clear what you mean by "the two straight 1 ohm resistors", but try this...

Since B and C are open circuits for this question, delete their respective 1 Ohm resistors. Then re-draw the circuit, with A at the top and D at the bottom. See if you can draw the resistors in a more normal configuration, using this simplification...
 
The only thing I can see is that the two straight 1 ohm resistors are in parallel , giving 1*1/1+1= 1/2 resistance.

There are no resistors directly in parallel so the above can't be right.

Do what berkeman said.
 
berkeman said:
It's not clear what you mean by "the two straight 1 ohm resistors", but try this...

Since B and C are open circuits for this question, delete their respective 1 Ohm resistors. Then re-draw the circuit, with A at the top and D at the bottom. See if you can draw the resistors in a more normal configuration, using this simplification...
Okay.
After deleting those two , I can see two pairs of resistors in series giving 2 each. Then these two 2 ohm resistors are in parallel , giving 1 ohm. Now these is in series with the remaining two 1 ohm resistors giving 3 ohm as the answer. Am I correct ?
 
I am sure that you are correct.
 
I agree.
 
According to Wheatstone bridge
Answer is 7/4 ohms that is 1.75 ohms
Am I correct ?
 
Kabir Nanda said:
According to Wheatstone bridge
Answer is 7/4 ohms that is 1.75 ohms
Am I correct ?
No. Show your work. Or better yet, start a new thread since this is a rather old thread (from 2013) and the Original Poster hasn't been logged in since 2015.
 
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