- #1

- 16

- 0

this question is part of my electronics CW, ive done it before, but briefly. and looking back at all my old notes ive realised that every single one ive done before has 2 sources and only 2 loops, whereas you can see from the image below that this has 3 and its getting me in quite a kerfuffle. help is appreciated

"With the calculated value of R1, determine the current through resistor R5 using mesh analysis. Using this current value, determine the voltage across resistor R5.

You need to clearly indicate the mesh current directions and voltage drop directions. Your answer should include Kirchhoff’s law Voltage (KVL) equations for each loop and method that you used for solving simultaneous equations. "

my attempt at the solution gets stuck at the KVL rule. i am fairly certain im wrong but so far ive gotten this far: left mesh=I1 top right mesh=I2 bottom left =I3

i believe all the loops are clockwise

I1= V=R1*(I1-I2)+R4*(I1-I3)

I2= 0=R5*(I2±I3)+R1*(I2-I1)+R5*I2

I3= 0=R3*I3+R4*(I3-I1)+R5(I3±I2)

can someone please give me a heads up how to keep this going as its really bothering me now.

regards ash kennard

EDIT: R20 was mean to be R2, but multisim wouldnt let me change it for some reason :S

EDIT: i think i have the KVL down now, but the places i have"±" i am confused which sign to have. an input on that for now would be awesome. cheers guys xxx

"With the calculated value of R1, determine the current through resistor R5 using mesh analysis. Using this current value, determine the voltage across resistor R5.

You need to clearly indicate the mesh current directions and voltage drop directions. Your answer should include Kirchhoff’s law Voltage (KVL) equations for each loop and method that you used for solving simultaneous equations. "

my attempt at the solution gets stuck at the KVL rule. i am fairly certain im wrong but so far ive gotten this far: left mesh=I1 top right mesh=I2 bottom left =I3

i believe all the loops are clockwise

I1= V=R1*(I1-I2)+R4*(I1-I3)

I2= 0=R5*(I2±I3)+R1*(I2-I1)+R5*I2

I3= 0=R3*I3+R4*(I3-I1)+R5(I3±I2)

can someone please give me a heads up how to keep this going as its really bothering me now.

regards ash kennard

EDIT: R20 was mean to be R2, but multisim wouldnt let me change it for some reason :S

EDIT: i think i have the KVL down now, but the places i have"±" i am confused which sign to have. an input on that for now would be awesome. cheers guys xxx

#### Attachments

Last edited: