1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Difficult : Calculate equivalent resistance of the circuit problem .

  1. Jun 25, 2013 #1
    1. The problem statement, all variables and given/known data

    Calculate the total equivalent resistance between A and D -
    ( All resistors are 1 ohm )

    2. Relevant equations

    3. 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 !
  2. jcsd
  3. Jun 25, 2013 #2


    User Avatar

    Staff: Mentor

    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...
  4. Jun 26, 2013 #3


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

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

    Do what berkeman said.
  5. Jun 26, 2013 #4
    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 ?
  6. Jun 26, 2013 #5
    I am sure that you are correct.
  7. Jun 26, 2013 #6


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    I agree.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted