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: Finding current in circuit

  1. Sep 2, 2013 #1
    I think the book is wrong.

    Why is the current (which they denote IL) equal to Vs/(Req)

    Where Vs = 458.3kV and Req is the equivalent resistance of the circuit equal to the sum of the two resistors in series ( Req = 220 + 20 = 240).

    In there equation they left out the the resistor of 20 ohmes

    Attached Files:

  2. jcsd
  3. Sep 2, 2013 #2
    No, the book answer is correct. They are finding the current in Rload by knowing Iload = Vload/Rload.
    Now that you know the current, you can find the voltage drop across the 20 okm line resistance. Then you can find the source voltage.
  4. Sep 3, 2013 #3
    Why is the current different through each resistor?
  5. Sep 3, 2013 #4


    User Avatar
    Science Advisor
    Homework Helper

    It's not. That's what barryj is saying. They are the same. But the voltage drop is only measured against the load resistance. You can use that to find the source voltage.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted