1. Not finding help here? Sign up for a free 30min 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!

Resistive Network. - nodal analysis

  1. Nov 9, 2014 #1
    1. The problem statement, all variables and given/known data
    http://learn.lboro.ac.uk/file.php/1844/Quiz_figures/Chins_Files/Q11.jpg





    In the above circuit



    V1=17 Volts

    V2=8.5 Volts

    V3=4.25 Volts

    I1= 4 Amps

    I2= 5 Amps

    R1=4.25 Ohms

    R3=6.375 Ohms

    R4=1.0625 Ohms

    R5=2.125 Ohms

    R6=2.125 Ohms



    Calculate the following:



    a) Magnitude of the current through R5:

    b) The resistance R2:

    a) Magnitude of the voltage across I1:


    2. Relevant equations


    3. The attempt at a solution
    I am really unsure on how to start this question, any starting tips would be great please, this was a tutorial set in my college class. Q11.jpg Q11.jpg
     
  2. jcsd
  3. Nov 9, 2014 #2

    NascentOxygen

    User Avatar

    Staff: Mentor

    Have you looked at where the given voltage V3 is located? :))
     
  4. Nov 9, 2014 #3
    what do you mean by that sorry?
     
  5. Nov 9, 2014 #4

    NascentOxygen

    User Avatar

    Staff: Mentor

    You're wanting guidance to answer part (a)?
     
  6. Nov 9, 2014 #5
    I think i know how to work out Part A - Im just guessing its Voltage divided by R?
    Its part b and c, that i am stuck with
     
  7. Nov 9, 2014 #6

    NascentOxygen

    User Avatar

    Staff: Mentor

    Guessing??

    Can you work out how many volts across R4?
    Hence, determine the current through R4 .... and so on, working your way around the circuit until you have determined all parameters needed to answer the questions.
     
  8. Nov 9, 2014 #7
    Sorry I'm confused now. Would I need nodal analysis for this and convert all of these to current sources?
     
  9. Nov 9, 2014 #8

    mfb

    User Avatar
    2016 Award

    Staff: Mentor

    You do not have to convert anything, and you can do it step by step. There is no need for multiple unknowns at the same time. NascentOxygen showed you the first two steps.
     
  10. Nov 9, 2014 #9

    NascentOxygen

    User Avatar

    Staff: Mentor

    Just use KVL to determine the voltage across R4.

    Then use Ohms Law, KCL and KVL to determine voltages and currents one by one. No formal analysis and no need for a matrix of simultaneous equations!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted