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: Electricity Circles question that's killing me

  1. Feb 23, 2004 #1
    Heya Folks,

    First I would like to apologize for my bad English - I live in Israel and our mother toungue is Hebrew here, I'll try my best though..

    Now I don't know how you call what we call Straght-Line Electricity Circles but basically I mean AC just not alternative ;)

    Anyways my problem is with the following circle:

    http://dgemu.suhost.com/physicu/1.gif [Broken]
    (the url is http://dgemu.suhost.com/physicu/1.gif [Broken] if you don't see it good).

    I'm told that the potential in P is 200 volt and I'm asked what's the potential in Q.

    Now I went by the (using $ as sigma):
    $E = $I*R
    equasion and I found that I is 20A, and then I found out that the potential from P to Q is 110v so I assume the potential in P is 310v - but that answer is wrong..

    I'm doing an online test and I only get TrUE of FALSE for my answers and I have no idea what is the correct question and how to get to it.

    Any help would be appreciated,
    - Ben
    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Feb 23, 2004 #2
    nvm I guess that was really stupid I should've done -110 and then it's 90 and not 310 - the correct answer is 90 - thanks for anyone who read this topic..
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook