0.1A discrepancy when summing currents in parallel circuit

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Mark Nussbaum

Homework Statement


Circuit schematic of a single node pair with resistors R1, R2, R3 and R4, a current source is, a dependent current source of 0.5 Vx, and currents i1 through i5 marked by arrows along branches above and below the line.


Homework Equations


V=IR
parallel resistance.

The Attempt at a Solution


All elements are in parallel (teacher confirmed this in explanation to the class). Beginning placing labels for nodes to the right of R1, A, B, C, D, and E (ending before R4) and redrawing it as the teacher showed to get us started...
Handwritten circuit analysis on paper: small schematic of resistors R1 to R4 with nodes A to E and dependent source Vx, above KCL and Ohm's law equations solving for Vx, I5 and branch currents i1 to i3.

Once I add the currents together in the original equation I end up with .1A left over...
(sorry about low quality don't know how to get it to a webpage.)
 
Attachments
  • Handwritten circuit schematic with nodes A to E and resistors R1 to R4 plus a voltage source, next to handwritten KCL and Ohm's law calculations giving currents of about 0.5527 A, 0.1023 A, 0.2126 A and 0.1043 A.
    upload_2017-9-16_2-49-32.png
    88.5 KB · Views: 619
  • Handwritten circuit diagram with nodes A through E and resistors R1 to R4, plus a meter, beside Kirchhoff current law and Ohm's law working; the total evaluates to Vx = 11.05585 V.
    upload_2017-9-16_2-51-15.png
    88.6 KB · Views: 618

Discussion

Mark Nussbaum, are you still working on this? You know the current from the .5 Vx source and you know the current through R4 (it's the same as I5); do you see how those two allow you to calculate I4?