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: Circuit with two terminals

  1. Feb 9, 2010 #1
    1. The problem statement, all variables and given/known data

    help please! i am trying to find V at terminal A with respect to B

    2. Relevant equations

    3. The attempt at a solution
    so this is my thought process:
    the answer should be 10 V because the voltage is the same for a parallel resistor, but the thing that throws me off is that terminal is has a resistance of 1 Ohm so i'm not sure if my answer is right. help please and thank you.
    Last edited: Feb 9, 2010
  2. jcsd
  3. Feb 9, 2010 #2
    That's incorrect. The 1 Ohm resistor is just a wire as there is no current flowing through it so it can be ignored. So now you basically just have that first loop. The voltage across terminals A and B is the same as the voltage across the 3 Ohm resistor, right? How can you find the voltage across that resistor?
  4. Feb 9, 2010 #3
    okay. with that info, i got the voltage across the 3Ohm resistor to be 6.00 A

    is this right?

    because i added 2 and 3 since it is in series so that gives total resistance
    V=IR for the 3Ohm resistor
    V=2(3) = 6
  5. Feb 9, 2010 #4
    Yep that's right. Also, if you want to verify your answer you could do a Voltage divider equation... V = 10V * (3 / (3+2) ) = 6 or KCL analysis at that top node so (V1 - 10V)/2 + (V1 - 0)/3 = 0 and then solve for V1 which ends up being 6V.

    Of course the way you did it is the easier way, I'm just showing you other approaches and verifying your answer :p
  6. Feb 9, 2010 #5
    thanks for the help. and i meant 6.00 V, not 6.00 A but i'm sure you figured that out
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook